Athena Widget Set - C Language Interface

X Consortium Standard

Chris D. Peterson

   formerly MIT X Consortium

   X Version 11, Release 7.7

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   Table of Contents

   1. Athena Widgets and The Intrinsics

        Introduction to the X Toolkit
        Terminology
        Underlying Model
        Conventions Used in this Manual
        Format of the Widget Reference Chapters
        Input Focus

   2. Using Widgets

        Using Widgets

              Setting the Locale
              Initializing the Toolkit
              Creating a Widget
              Common Resources
              Resource Conversions
              Realizing a Widget
              Processing Events
              Standard Widget Manipulation Functions
              Using the Client Callback Interface
              Programming Considerations
              Example Programs

   3. Simple Widgets

        Command Widget

              Resources
              Command Actions

        Grip Widget

              Resources
              Grip Actions

        Label Widget

              Resources

        List Widget

              Resources
              List Actions
              List Callbacks
              Changing the List
              Highlighting an Item
              Unhighlighting an Item
              Retrieving the Currently Selected Item
              Restrictions

        Panner Widget

              Resources
              Panner Actions
              Panner Callbacks

        Repeater Widget

              Resources
              Repeater Actions

        Scrollbar Widget

              Resources
              Scrollbar Actions
              Scrollbar Callbacks
              Convenience Routines
              Setting Float Resources

        Simple Widget

              Resources

        StripChart Widget

              Resources
              Getting the StripChart Value

        Toggle Widget

              Resources
              Toggle Actions
              Toggle Actions
              Radio Groups
              Convenience Routines

   4. Menus

        Using the Menus
        Sme Object

              Resources
              Subclassing the Sme Object

        SmeBSB Object

              Resources

        SmeLine Object

              Resources

   5. Text Widgets

        Text Widget for Users

              Default Key Bindings
              Search and Replace
              File Insertion
              Text Selections for Users

        Text Widget Actions

              Cursor Movement Actions\fP
              Delete Actions
              Selection Actions
              The New Line Actions
              Kill and Actions
              Miscellaneous Actions
              Text Selections for Application Programmers

        Default Translation Bindings
        Text Functions

              Selecting Text
              Unhighlighting Text
              Getting Current Text Selection
              Replacing Text
              Searching for Text
              Redisplaying Text
              Resources Convenience Routines

        Customizing the Text Widget
        Text Widget

              Resources

        TextSink Object

              Resources
              Subclassing the TextSink

        TextSrc Object

              Resources
              Subclassing the TextSrc

        Ascii Sink Object and Multi Sink Object

              Resources

        Ascii Source Object and Multi Source Object

              Resources
              Convenience Routines

        Ascii Text Widget

              Resources

   6. Composite and Constraint Widgets

        Box Widget

              Resources
              Layout Semantics

        Dialog Widget

              Resources
              Constraint Resources
              Layout Semantics
              Automatically Created Children.
              Convenience Routines

        Form Widget

              Resources
              Constraint Resources
              Layout Semantics
              Convenience Routines

        Paned Widget

              Using the Paned Widget
              Resources
              Constraint Resources
              Layout Semantics
              Grip Translations
              Convenience Routines

        Porthole Widget

              Resources
              Layout Semantics
              Porthole Callbacks

        Tree Widget

              Resources
              Constraint Resources
              Layout Semantics
              Convenience Routines

        Viewport Widget

              Resources
              Layout Semantics

   7. Creating New Widgets (Subclassing)

        Public Header File
        Private Header File
        Widget Source File

   8. Acknowledgments

Chapter 1. Athena Widgets and The Intrinsics

   Table of Contents

   Introduction to the X Toolkit
   Terminology
   Underlying Model
   Conventions Used in this Manual
   Format of the Widget Reference Chapters
   Input Focus

   The X Toolkit is made up of two distinct pieces, the Xt
   Intrinsics and a widget set. The Athena widget set is a sample
   implementation of a widget set built upon the Intrinsics. In
   the X Toolkit, a widget is the combination of an X window or
   subwindow and its associated input and output semantics.

   Because the Intrinsics provide the same basic functionality to
   all widget sets it may be possible to use widgets from the
   Athena widget set with other widget sets based upon the
   Intrinsics. Since widget sets may also implement private
   protocols, all functionality may not be available when mixing
   and matching widget sets. For information about the Intrinsics,
   see the X Toolkit Intrinsics - C Language Interface.

   The Athena widget set is a library package layered on top of
   the Intrinsics and Xlib that provides a set of user interface
   tools sufficient to build a wide variety of applications. This
   layer extends the basic abstractions provided by X and provides
   the next layer of functionality primarily by supplying a
   cohesive set of sample widgets. Although the Intrinsics are a
   Consortium standard, there is no standard widget set.

   To the extent possible, the Intrinsics are "policy-free". The
   application environment and widget set, not the Intrinsics,
   define, implement, and enforce:
     * Policy
     * Consistency
     * Style

   Each individual widget implementation defines its own policy.
   The X Toolkit design allows for, but does not necessarily
   encourage, the free mixing of radically differing widget
   implementations.

Introduction to the X Toolkit

   The X Toolkit provides tools that simplify the design of
   application user interfaces in the X Window System programming
   environment. It assists application programmers by providing a
   set of common underlying user-interface functions. It also lets
   widget programmers modify existing widgets, by subclassing, or
   add new widgets. By using the X Toolkit in their applications,
   programmers can present a similar user interface across
   applications to all workstation users.

   The X Toolkit consists of:
     * A set of Intrinsics functions for building widgets
     * An architectural model for constructing widgets
     * A widget set for application programming

   While the majority of the Intrinsics functions are intended for
   the widget programmer, a subset of the Intrinsics functions are
   to be used by application programmers (see X Toolkit Intrinsics
   - C Language Interface). The architectural model lets the
   widget programmer design new widgets by using the Intrinsics
   and by combining other widgets. The application interface
   layers built on top of the X Toolkit include a coordinated set
   of widgets and composition policies. Some of these widgets and
   policies are specific to a single application domain, and
   others are common to a variety of applications.

   The remainder of this chapter discusses the X Toolkit and
   Athena widget set:
     * Terminology
     * Model
     * Conventions used in this manual
     * Format of the Widget Reference Chapters

Terminology

   In addition to the terms already defined for X programming (see
   Xlib - C Language Interface), the following terms are specific
   to the Intrinsics and Athena widget set and used throughout
   this document.

   Application programmer
     * A programmer who uses the X Toolkit to produce an
       application user interface.

   Child
     * A widget that is contained within another "parent" widget.

   Class
     * The general group to which a specific object belongs.

   Client
     * A function that uses a widget in an application or for
       composing other widgets.

   FullName
     * The name of a widget instance appended to the full name of
       its parent.

   Instance
     * A specific widget object as opposed to a general widget
       class.

   Method
     * A function or procedure implemented by a widget class.

   Name
     * The name that is specific to an instance of a widget for a
       given client. This name is specified at creation time and
       cannot be modified.

   Object
     * A data abstraction consisting of private data and private
       and public functions that operate on the private data.
       Users of the abstraction can interact with the object only
       through calls to the object's public functions. In the X
       Toolkit, some of the object's public functions are called
       directly by the application, while others are called
       indirectly when the application calls the common Intrinsics
       functions. In general, if a function is common to all
       widgets, an application uses a single Intrinsics function
       to invoke the function for all types of widgets. If a
       function is unique to a single widget type, the widget
       exports the function.

   Parent
     * A widget that contains at least one other ("child") widget.
       A parent widget is also known as a composite widget.

   Resource
     * A named piece of data in a widget that can be set by a
       client, by an application, or by user defaults.

   Superclass
     * A larger class of which a specific class is a member. All
       members of a class are also members of the superclass.

   User
     * A person interacting with a workstation.

   Widget
     * An object providing a user-interface abstraction (for
       example, a Scrollbar widget).

   Widget class
     * The general group to which a specific widget belongs,
       otherwise known as the type of the widget.

   Widget programmer
     * A programmer who adds new widgets to the X Toolkit.

Underlying Model

   The underlying architectural model is based on the following
   premises:
     *
     * Every user-interface widget is associated with an X window.
       The X window ID for a widget is readily available from the
       widget. Standard Xlib calls can be used by widgets for many
       of their input and output operations.
     *
     * The data for every widget is private to the widget and its
       subclasses. That is, the data is neither directly
       accessible nor visible outside of the module implementing
       the widget. All program interaction with the widget is
       performed by a set of operations (methods) that are defined
       for the widget.
     *
     * Widget semantics are clearly separated from widget layout
       geometry. Widgets are concerned with implementing specific
       user-interface semantics. They have little control over
       issues such as their size or placement relative to other
       widget peers. Mechanisms are provided for associating
       geometric managers with widgets and for widgets to make
       suggestions about their own geometry.

Conventions Used in this Manual

     * All resources available to the widgets are listed with each
       widget. Many of these are available to more than one widget
       class due to the object oriented nature of the Intrinsics.
       The new resources for each widget are listed in bold text,
       and the inherited resources are listed in plain text.
     * Global symbols are printed in bold and can be function
       names, symbols defined in include files, or structure
       names. Arguments are printed in italics.
     * Each function is introduced by a general discussion that
       distinguishes it from other functions. The function
       declaration itself follows, and each argument is
       specifically explained. General discussion of the function,
       if any is required, follows the arguments. Where
       applicable, the last paragraph of the explanation lists the
       return values of the function.
     * To eliminate any ambiguity between those arguments that you
       pass and those that a function returns to you, the
       explanations for all arguments that you pass start with the
       word specifies or, in the case of multiple arguments, the
       word specify. The explanations for all arguments that are
       returned to you start with the word returns or, in the case
       of multiple arguments, the word return. The explanations
       for all arguments that you can pass and are returned start
       with the words specifies and returns.
     * Any pointer to a structure that is used to return a value
       is designated as such by the _return suffix as part of its
       name. All other pointers passed to these functions are used
       for reading only. A few arguments use pointers to
       structures that are used for both input and output and are
       indicated by using the _in_out suffix.

Format of the Widget Reference Chapters

   The majority of this document is a reference guide for the
   Athena widget set. Chapters three through six give the
   programmer all information necessary to use the widgets. The
   layout of the chapters follows a specific pattern to allow the
   programmer to easily find the desired information.

   The first few pages of every chapter give an overview of the
   widgets in that section. Widgets are grouped into chapters by
   functionality.

   "Chapter

   Simple Widgets

   "Chapter

   Menus

   "Chapter

   Text Widgets

   "Chapter

   Composite and Constraint Widget

   Following the introduction will be a description of each widget
   in that chapter. When no functional grouping is obvious the
   widgets are listed in alphabetical order, such as in chapters
   three and six.

   The first section of each widget's description is a table that
   contains general information about this widget class. Here is
   the table for the Box widget, and an explanation of all the
   entries.



Application Header file <X11/Xaw/Box.h>
Class Header file       <X11/Xaw/BoxP.h>
Class           boxWidgetClass
Class Name      Box
Superclass      Composite


   Application Header File

   This file must be included when an application uses this
   widget. It usually contains the class definition, and some
   resource macros. This is often called the ``public'' header
   file.

   Class Header File

   This file will only be used by widget programmers. It will need
   to be included by any widget that subclasses this widget. This
   is often called the ``private'' header file.

   Class

   This is the widget class of this widget. This global symbol is
   passed to XtCreateWidget so that the Intrinsics will know which
   type of widget to create.

   Class Name

   This is the resource name of this class. This name can be used
   in a resource file to match any widget of this class.

   Superclass

   This is the superclass that this widget class is descended
   from. If you understand how the superclass works it will allow
   you to more quickly understand what this widget does, since
   much of its functionality may be inherited from its superclass.

   After this table follows a general description of the default
   behavior of this widget, as seen by the user. In many cases
   this functionality may be overridden by the application
   programmer, or by the user.

   The next section is a table showing the name, class, type and
   default value of each resource that is available to this
   widget. There is also a column containing notes describing
   special restrictions placed upon individual resources.

   A

   This resource may be automatically adjusted when another
   resource is changed.

   C

   This resource is only settable at widget creation time, and may
   not be modified with XtSetValues.

   D

   Do not modify this resource. While setting this resource will
   work, it can cause unexpected behavior. When this symbol
   appears there is another, preferred, interface provided by the
   X Toolkit.

   R

   This resource is READ-ONLY, and may not be modified.

   After the resource table is a detailed description of every
   resource available to that widget. Many of these are redundant,
   but printing them with each widget saves page flipping. The
   names of the resources that are inherited are printed in plain
   text, while the names of the resources that are new to this
   class are printed in bold. If you have already read the
   description of the superclass you need only pay attention to
   the resources printed in bold.

   For each composite widget there is a section on layout
   semantics that follows the resource description. This section
   will describe the effect of constraint resources on the layout
   of the children, as well as a general description of where it
   prefers to place its children.

   Descriptions of default translations and action routines come
   next, for widgets to which they apply. The last item in each
   widget's documentation is the description of all convenience
   routines provided by the widget.

Input Focus

   The Intrinsics define a resource on all Shell widgets that
   interact with the window manager called input. This resource
   requests the assistance of window manager in acquiring the
   input focus. The resource defaults to False in the Intrinsics,
   but is redefined to default to True when an application is
   using the Athena widget set. An application programmer may
   override this default and set the resource back to False if the
   application does not need the window manager to give it the
   input focus. See the X Toolkit Intrinsics - C Language
   Interface for details on the input resource.

Chapter 2. Using Widgets

   Table of Contents

   Using Widgets

        Setting the Locale
        Initializing the Toolkit
        Creating a Widget
        Common Resources
        Resource Conversions
        Realizing a Widget
        Processing Events
        Standard Widget Manipulation Functions
        Using the Client Callback Interface
        Programming Considerations
        Example Programs

Using Widgets

   Widgets serve as the primary tools for building a user
   interface or application environment. The Athena widget set
   consists of primitive widgets that contain no children (for
   example, a command button) and composite widgets which may
   contain one or more widget children (for example, a Box
   widget).

   The remaining chapters explain the widgets that are provided by
   the Athena widget set. These user-interface components serve as
   an interface for application programmers who do not want to
   implement their own widgets. In addition, they serve as a
   starting point for those widget programmers who, using the
   Intrinsics mechanisms, want to implement alternative
   application programming interfaces.

   This chapter is a brief introduction to widget programming. The
   examples provided use the Athena widgets, though most of the
   concepts will apply to all widget sets. Although there are
   several programming interfaces to the X Toolkit, only one is
   described here. A full description of the programming interface
   is provided in the document X Toolkit Intrinsics - C Language
   Interface.

Setting the Locale

   If it is desirable that the application take advantage of
   internationalization (i18n), you must establish locale with
   XtSetLanguageProc before XtDisplayInitialize or XtAppInitialize
   is called. For full details, please refer to the document X
   Toolkit Intrinsics - C Language Interface, section 2.2.
   However, the following simplest-case call is sufficient in many
   or most applications.



        XtSetLanguageProc(NULL, NULL, NULL);

   Most notably, this will affect the Standard C locale, determine
   which resource files will be loaded, and what fonts will be
   required of FontSet specifications. In many cases, the addition
   of this line is the only source change required to
   internationalize Xaw programs, and will not disturb the
   function of programs in the default "C" locale.

Initializing the Toolkit

   You must call a toolkit initialization function before invoking
   any other toolkit routines (besides locale setting, above).
   XtAppInitialize opens the X server connection, parses the
   command line, and creates an initial widget that will serve as
   the root of a tree of widgets created by this application.

   Widgetfsfunc XtAppInitialize(XtAppContext app_context_return,
   String application_class, XrmOptionDescRec options, Cardinal
   num_options, int *argc_in_out, String *argv_in_out, String
   *fallback_resources, ArgList args, Cardinal num_args);

   app_con_return

   Returns the application context of this application, if
   non-NULL.

   application_class

   Specifies the class name of this application, which is usually
   the generic name for all instances of this application. A
   useful convention is to form the class name by capitalizing the
   first letter of the application name. For example, the
   application named ``xman'' has a class name of ``Xman''.

   options

   Specifies how to parse the command line for any
   application-specific resources. The options argument is passed
   as a parameter to XrmParseCommand. For further information, see
   Xlib - C Language Interface.

   num_options

   Specifies the number of entries in the options list.

   argc_in_out

   Specifies a pointer to the number of command line parameters.

   argv_in_out

   Specifies the command line parameters.

   fallback_resources

   Specifies resource values to be used if the site-wide
   application class defaults file cannot be opened, or NULL.

   args

   Specifies the argument list to use when creating the
   Application shell.

   num_args

   Specifies the number of arguments in args.

   This function will remove the command line arguments that the
   toolkit reads from argc_in_out, and argv_in_out. It will then
   attempt to open the display. If the display cannot be opened,
   an error message is issued and XtAppInitialize terminates the
   application. Once the display is opened, all resources are read
   from the locations specified by the Intrinsics. This function
   returns an ApplicationShell widget to be used as the root of
   the application's widget tree.

Creating a Widget

   Creating a widget is a three-step process. First, the widget
   instance is allocated, and various instance-specific attributes
   are set by using XtCreateWidget. Second, the widget's parent is
   informed of the new child by using XtManageChild. Finally, X
   windows are created for the parent and all its children by
   using XtRealizeWidget and specifying the top-most widget. The
   first two steps can be combined by using XtCreateManagedWidget.
   In addition, XtRealizeWidget is automatically called when the
   child becomes managed if the parent is already realized.

   To allocate, initialize, and manage a widget, use
   XtCreateManagedWidget .

   Widgetfsfunc XtCreateManagedWidget(String name, WidgetClass
   widget_class, Widget parent, ArgList args, Cardinal num_args);

   name

   Specifies the instance name for the created widget that is used
   for retrieving widget resources.

   widget_class

   Specifies the widget class pointer for the created widget.

   parent

   Specifies the parent widget ID.

   args

   Specifies the argument list. The argument list is a
   variable-length list composed of name and value pairs that
   contain information pertaining to the specific widget instance
   being created. For further information, see Section 2.7.2.

   num_args

   Specifies the number of arguments in the argument list. If the
   num_args is zero, the argument list is never referenced.

   When a widget instance is successfully created, the widget
   identifier is returned to the application. If an error is
   encountered, the XtError routine is invoked to inform the user
   of the error.

   For further information, see X Toolkit Intrinsics - C Language
   Interface.

Common Resources

   Although a widget can have unique arguments that it
   understands, all widgets have common arguments that provide
   some regularity of operation. The common arguments allow
   arbitrary widgets to be managed by higher-level components
   without regard for the individual widget type. Widgets will
   ignore any argument that they do not understand.

   The following resources are retrieved from the argument list or
   from the resource database by all of the Athena widgets:
      Name              Class             Type          Default Value
  accelerators      Accelerators    AcceleratorTable        NULL
ancestorSensitive AncestorSensitive     Boolean             True
   background        Background          Pixel       XtDefaultBackground
backgroundPixmap       Pixmap            Pixmap      XtUnspecifiedPixmap
   borderColor       BorderColor         Pixel       XtDefaultForeground
  borderPixmap         Pixmap            Pixmap      XtUnspecifiedPixmap
   borderWidth       BorderWidth       Dimension              1
    colormap          Colormap          Colormap      Parent's Colormap
      depth             Depth             int          Parent's Depth
 destroyCallback      Callback       XtCallbackList         NULL
     height            Height          Dimension      widget dependent
mappedWhenManaged MappedWhenManaged     Boolean             True
     screen            Screen            Screen        Parent's Screen
    sensitive         Sensitive         Boolean             True
  translations      Translations    TranslationTable  widget dependent
      width             Width          Dimension      widget dependent
        x             Position          Position              0
        y             Position          Position              0

   The following additional resources are retrieved from the
   argument list or from the resource database by many of the
   Athena widgets:
         Name           Class         Type         Default Value
       callback       Callback   XtCallbackList        NULL
        cursor         Cursor        Cursor      widget dependent
      foreground     Foreground      Pixel      XtDefaultForeground
   insensitiveBorder Insensitive     Pixmap         GreyPixmap

Resource Conversions

   Most resources in the Athena widget set have a converter
   registered that will translate the string in a resource file to
   the correct internal representation. While some are obvious
   (string to integer, for example), others need specific mention
   of the allowable values. Three general converters are described
   here:
     * Cursor
     * Pixel
     * Bitmap

   Many widgets have defined special converters that apply only to
   that widget. When these occur, the documentation section for
   that widget will describe the converter.

Cursor Conversion

   The value for the cursorName resource is specified in the
   resource database as a string, and is of the following forms:
     * A standard X cursor name from < X11/cursorfont.h >. The
       names in cursorfont.h each describe a specific cursor. The
       resource names for these cursors are exactly like the names
       in this file except the XC_ is not used. The cursor
       definition XC_gumby has a resource name of gumby.
     * Glyphs, as in FONT font-name glyph-index [[ font-name ]
       glyph-index ]. The first font and glyph specify the cursor
       source pixmap. The second font and glyph specify the cursor
       mask pixmap. The mask font defaults to the source font, and
       the mask glyph index defaults to the source glyph index.
     * A relative or absolute file name. If a relative or absolute
       file name is specified, that file is used to create the
       source pixmap. Then the string "Mask" is appended to locate
       the cursor mask pixmap. If the "Mask" file does not exist,
       the suffix "msk" is tried. If "msk" fails, no cursor mask
       will be used. If the filename does not start with '/' or
       './' the the bitmap file path is used (see section 2.4.3).

Pixel Conversion

   The string-to-pixel converter takes any name that is acceptable
   to XParseColor (see Xlib - C Language Interface). In addition
   this routine understands the special toolkit symbols
   `XtDefaultForeground' and `XtDefaultBackground', described in X
   Toolkit Intrinsics - C Language Interface. In short the
   acceptable pixel names are:
     * Any color name for the rgb.txt file (typically in the
       directory /usr/lib/X11 on POSIX systems).
     * A numeric specification of the form #<red><green><blue>
       where these numeric values are hexadecimal digits (both
       upper and lower case).
     * The special strings `XtDefaultForeground' and
       `XtDefaultBackground'

Bitmap Conversion

   The string-to-bitmap converter attempts to locate a file
   containing bitmap data whose name is specified by the input
   string. If the file name is relative (i.e. does not begin with
   / or ./), the directories to be searched are specified in the
   bitmapFilePath resource--class BitmapFilePath. This resource
   specifies a colon (:) separated list of directories that will
   be searched for the named bitmap or cursor glyph (see section
   2.4.1). The bitmapFilePath resource is global to the
   application, and may not be specified differently for each
   widget that wishes to convert a cursor to bitmap. In addition
   to the directories specified in the bitmapFilePath resource a
   default directory is searched. When using POSIX the default
   directory is /usr/include/X11/bitmaps .

Realizing a Widget

   The XtRealizeWidget function performs two tasks:
     * Calculates the geometry constraints of all managed
       descendants of this widget. The actual calculation is put
       off until realize time for performance reasons.
     * Creates an X window for the widget and, if it is a
       composite widget, realizes each of its managed children.
       voidfsfunc XtRealizeWidget(Widget w);
     * Specifies the widget.

   For further information about this function, see the X Toolkit
   Intrinsics - C Language Interface.

Processing Events

   Now that the application has created, managed and realized its
   widgets, it is ready to process the events that will be
   delivered by the X Server to this client. A function call that
   will process the events is XtAppMainLoop.

   voidfsfunc XtAppMainLoop(XtAppContext app_context);

   app_context

   Specifies the application context of this application. The
   value is normally returned by XtAppInitialize.

   This function never returns: it is an infinite loop that
   processes the X events. User input can be handled through
   callback procedures and application defined action routines.
   More details are provided in X Toolkit Intrinsics - C Language
   Interface.

Standard Widget Manipulation Functions

   After a widget has been created, a client can interact with
   that widget by calling one of the standard widget manipulation
   routines provided by the Intrinsics, or a widget class-specific
   manipulation routine.

   The Intrinsics provide generic routines to give the application
   programmer access to a set of standard widget functions. The
   common widget routines let an application or composite widget
   perform the following operations on widgets without requiring
   explicit knowledge of the widget type.
     * Control the mapping of widget windows
     * Destroy a widget instance
     * Obtain an argument value
     * Set an argument value

Mapping Widgets

   By default, widget windows are mapped (made viewable)
   automatically by XtRealizeWidget. This behavior can be disabled
   by using XtSetMappedWhenManaged, making the client responsible
   for calling XtMapWidget to make the widget viewable.

   voidfsfunc XtSetMappedWhenManaged(Widget w, Boolean
   map_when_managed);

   w

   Specifies the widget.

   map_when_managed

   Specifies the new value. If map_when_managed is True, the
   widget is mapped automatically when it is realized. If
   map_when_managed is False, the client must call XtMapWidget or
   make a second call to XtSetMappedWhenManaged to cause the child
   window to be mapped.

   The definition for XtMapWidget is:

   voidfsfunc XtMapWidget(Widget w);

   w

   Specifies the widget.

   When you are creating several children in sequence for a
   previously realized common parent it is generally more
   efficient to construct a list of children as they are created
   (using XtCreateWidget) and then use XtManageChildren to request
   that their parent managed them all at once. By managing a list
   of children at one time, the parent can avoid wasteful
   duplication of geometry processing and the associated ``screen
   flash''.

   voidfsfunc XtManageChildren(WidgetList children, Cardinal
   num_children);

   children

   Specifies a list of children to add.

   num_children

   Specifies the number of children to add.

   If the parent is already visible on the screen, it is
   especially important to batch updates so that the minimum
   amount of visible window reconfiguration is performed.

   For further information about these functions, see the X
   Toolkit Intrinsics - C Language Interface.

Destroying Widgets

   To destroy a widget instance of any type, use XtDestroyWidget

   voidfsfunc XtDestroyWidget(Widget w);

   w

   Specifies the widget.

   XtDestroyWidget destroys the widget and recursively destroys
   any children that it may have, including the windows created by
   its children. After calling XtDestroyWidget , no further
   references should be made to the widget or any children that
   the destroyed widget may have had.

Retrieving Widget Resource Values

   To retrieve the current value of a resource attribute
   associated with a widget instance, use XtGetValues .

   voidfsfunc XtGetValues(Widget w, ArgList args, Cardinal
   num_args);

   w

   Specifies the widget.

   args

   Specifies a variable-length argument list of name and address
   pairs that contain the resource name and the address into which
   the resource value is stored.

   num_args

   Specifies the number of arguments in the argument list.

   The arguments and values passed in the argument list are
   dependent on the widget. Note that the caller is responsible
   for providing space into which the returned resource value is
   copied; the ArgList contains a pointer to this storage (e.g. x
   and y must be allocated as Position). For further information,
   see the X Toolkit Intrinsics - C Language Interface.

Modifying Widget Resource Values

   To modify the current value of a resource attribute associated
   with a widget instance, use XtSetValues .

   voidfsfunc XtSetValues(Widget w, ArgList args, Cardinal
   num_args);

   w

   Specifies the widget.

   args

   Specifies an array of name and value pairs that contain the
   arguments to be modified and their new values.

   num_args

   Specifies the number of arguments in the argument list.

   The arguments and values that are passed will depend on the
   widget being modified. Some widgets may not allow certain
   resources to be modified after the widget instance has been
   created or realized. No notification is given if any part of a
   XtSetValues request is ignored.

   For further information about these functions, see the X
   Toolkit Intrinsics - C Language Interface. The argument list
   entry for XtGetValues specifies the address to which the caller
   wants the value copied. The argument list entry for XtSetValues
   , however, contains the new value itself, if the size of value
   is less than sizeof(XtArgVal) (architecture dependent, but at
   least sizeof(long)); otherwise, it is a pointer to the value.
   String resources are always passed as pointers, regardless of
   the length of the string.

Using the Client Callback Interface

   Widgets can communicate changes in their state to their clients
   by means of a callback facility. The format for a client's
   callback handler is:

   voidfsfunc CallbackProc(Widget w, XtPointer client_data,
   XtPointer call_data);

   w

   Specifies widget for which the callback is registered.

   client_data

   Specifies arbitrary client-supplied data that the widget should
   pass back to the client when the widget executes the client's
   callback procedure. This is a way for the client registering
   the callback to also register client-specific data: a pointer
   to additional information about the widget, a reason for
   invoking the callback, and so on. If no additional information
   is necessary, NULL may be passed as this argument. This field
   is also frequently known as the closure.

   call_data

   Specifies any callback-specific data the widget wants to pass
   to the client. For example, when Scrollbar executes its
   jumpProc callback list, it passes the current position of the
   thumb in call_data.

   Callbacks can be registered either by creating an argument
   containing the callback list described below or by using the
   special convenience routines XtAddCallback and XtAddCallbacks.
   When the widget is created, a pointer to a list of callback
   procedure and data pairs can be passed in the argument list to
   XtCreateWidget . The list is of type XtCallbackList :



typedef struct {
        XtCallbackProc callback;
        XtPointer closure;
} XtCallbackRec, *XtCallbackList;

   The callback list must be allocated and initialized before
   calling XtCreateWidget . The end of the list is identified by
   an entry containing NULL in callback and closure. Once the
   widget is created, the client can change or de-allocate this
   list; the widget itself makes no further reference to it. The
   closure field contains the client_data passed to the callback
   when the callback list is executed.

   The second method for registering callbacks is to use
   XtAddCallback after the widget has been created.

   voidfsfunc XtAddCallback(Widget w, String callback_name,
   XtCallbackProc callback, XtPointer client_data);

   w

   Specifies the widget to add the callback to.

   callback_name

   Specifies the callback list within the widget to append to.

   callback

   Specifies the callback procedure to add.

   client_data

   Specifies the data to be passed to the callback when it is
   invoked.

   XtAddCallback adds the specified callback to the list for the
   named widget.

   All widgets provide a callback list named destroyCallback where
   clients can register procedures that are to be executed when
   the widget is destroyed. The destroy callbacks are executed
   when the widget or an ancestor is destroyed. The call_data
   argument is unused for destroy callbacks.

Programming Considerations

   This section provides some guidelines on how to set up an
   application program that uses the X Toolkit.

Writing Applications

   When writing an application that uses the X Toolkit, you should
   make sure that your application performs the following:
    1. Include < X11/Intrinsic.h > in your application programs.
       This header file automatically includes < X11/Xlib.h >, so
       all Xlib functions also are defined. It may also be
       necessary to include < X11/StringDefs.h > when setting up
       argument lists, as many of the XtNsomething definitions are
       only defined in this file.
    2. Include the widget-specific header files for each widget
       type that you need to use. For example, < X11/Xaw/Label.h >
       and < X11/Xaw/Command.h >.
    3. Call the XtAppInitialize function before invoking any other
       toolkit or Xlib functions. For further information, see
       Section 2.1 and the X Toolkit Intrinsics - C Language
       Interface.
    4. To pass attributes to the widget creation routines that
       will override any site or user customizations, set up
       argument lists. In this document, a list of valid argument
       names is provided in the discussion of each widget. The
       names each have a global symbol defined that begins with
       XtN to help catch spelling errors. For example, XtNlabel is
       defined for the label resource of many widgets.
    5. For further information, see Section 2.9.2.2.
    6. When the argument list is set up, create the widget with
       the XtCreateManagedWidget function. For further
       information, see Section 2.2 and the X Toolkit Intrinsics -
       C Language Interface.
    7. If the widget has any callback routines, set by the
       XtNcallback argument or the XtAddCallback function, declare
       these routines within the application.
    8. After creating the initial widget hierarchy, windows must
       be created for each widget by calling XtRealizeWidget on
       the top level widget.
    9. Most applications now sit in a loop processing events using
       XtAppMainLoop , for example:
   10.
XtCreateManagedWidget(name, class, parent, args, num_args);
XtRealizeWidget(shell);
XtAppMainLoop(app_context);

   11. For information about this function, see the X Toolkit
       Intrinsics - C Language Interface.
   12. Link your application with libXaw (the Athena widgets),
       libXmu (miscellaneous utilities), libXt (the X Toolkit
       Intrinsics), libSM (Session Management), libICE
       (Inter-Client Exchange), libXext (the extension library
       needed for the shape extension code which allows rounded
       Command buttons), and libX11 (the core X library). The
       following provides a sample command line:
   13.
cc -o application application.c \-lXaw \-lXmu \-lXt \
\-lSM \-lICE \-lXext \-lX11

Changing Resource Values

   The Intrinsics support two methods of changing the default
   resource values; the resource manager, and an argument list
   passed into XtCreateWidget. While resources values will get
   updated no matter which method you use, the two methods provide
   slightly different functionality.

   Resource Manager

   This method picks up resource definitions described in Xlib - C
   Language Interface from many different locations at run time.
   The locations most important to the application programmer are
   the fallback resources and the app-defaults file, (see X
   Toolkit Intrinsics - C Language Interface for the complete
   list). Since these resource are loaded at run time, they can be
   overridden by the user, allowing an application to be
   customized to fit the particular needs of each individual user.
   These values can also be modified without the need to rebuild
   the application, allowing rapid prototyping of user interfaces.
   Application programmers should use resources in preference to
   hard-coded values whenever possible.

   Argument Lists

   The values passed into the widget at creation time via an
   argument list cannot be modified by the user, and allow no
   opportunity for customization. It is used to set resources that
   cannot be specified as strings (e.g. callback lists) or
   resources that should not be overridden (e.g. window depth) by
   the user.

Specifying Resources

   It is important for all X Toolkit application programmers to
   understand how to use the X Resource Manager to specify
   resources for widgets in an X application. This section will
   describe the most common methods used to specify these
   resources, and how to use the X Resource manager.

   Xrdb

   The xrdb utility may be used to load a file containing
   resources into the X server. Once the resources are loaded, the
   resources will affect any new applications started on the
   display that they were loaded onto.

   Application Defaults

   The application defaults (app-defaults) file (normally in
   /usr/lib/X11/app-defaults/classname) for an application is
   loaded whenever the application is started.

   The resource specification has two colon-separated parts, a
   name, and a value. The value is a string whose format is
   dependent on the resource specified by name. Name is
   constructed by appending a resource name to a full widget name.

   The full widget name is a list of the name of every ancestor of
   the desired widget separated by periods (.). Each widget also
   has a class associated with it. A class is a type of widget
   (e.g. Label or Scrollbar or Box). Notice that class names, by
   convention, begin with capital letters and instance names begin
   with lower case letters. The class of any widget may be used in
   place of its name in a resource specification. Here are a few
   examples:

   xman.form.button1

   This is a fully specified resource name, and will affect only
   widgets called button1 that are children of widgets called form
   that are children of applications named xman. (Note that while
   typically two widgets that are siblings will have different
   names, it is not prohibited.)

   Xman.Form.Command

   This will match any Command widget that is a child of a Form
   widget that is itself a child of an application of class Xman.

   Xman.Form.button1

   This is a mixed resource name with both widget names and
   classes specified.

   This syntax allows an application programmer to specify any
   widget in the widget tree. To match more than one widget (for
   example a user may want to make all Command buttons blue), use
   an asterisk (*) instead of a period. When an asterisk is used,
   any number of widgets (including zero) may exist between the
   two widget names. For example:

   Xman*Command

   This matches all Command widgets in the Xman application.

   Foo*button1

   This matches any widget in the Foo application that is named
   button1.

   The root of all application widget trees is the widget returned
   by XtAppInitialize. Even though this is actually an
   ApplicationShell widget, the toolkit replaces its widget class
   with the class name of the application. The name of this widget
   is either the name used to invoke the application (argv[0]) or
   the name of the application specified using the standard -name
   command line option supported by the Intrinsics.

   The last step in constructing the resource name is to append
   the name of the resource with either a period or asterisk to
   the full or partial widget name already constructed.

   *foreground:Blue

   Specifies that all widgets in all applications will have a
   foreground color of blue.

   Xman*borderWidth:10

   Specifies that all widgets in an application whose class is
   Xman will have a border width of 10 (pixels).

   xman.form.button1.label:Testing

   Specifies that a particular widget in the xman application will
   have a label named Testing.

   An exclamation point (!) in the first column of a line
   indicates that the rest of the line should be treated as a
   comment.

   Final Words

   The Resource manager is a powerful tool that can be used very
   effectively to customize X Toolkit applications at run time by
   either the application programmer or the user. Some final
   points to note:
     * An application programmer may add new resources to their
       application. These resources are associated with the global
       application, and not any particular widget. The X Toolkit
       function used for adding the application resources is
       XtGetApplicationResources.
     * Be careful when creating resource files. Since widgets will
       ignore resources that they do not understand, any spelling
       errors will cause a resource to have no effect.
     * Only one resource line will match any given resource. There
       is a set of precedence rules, which take the following
       general stance.
     *
          + More specific overrides less specific, thus period
            always overrides asterisk.
          + Names on the left are more specific and override names
            on the right.
          + When resource specifications are exactly the same,
            user defaults will override program defaults.

   For a complete explanation of the rules of precedence, and
   other specific topics see X Toolkit Intrinsics - C Language
   Interface and Xlib - C Language Interface.

Creating Argument Lists

   To set up an argument list for the inline specification of
   widget attributes, you may use any of the four approaches
   discussed in this section. Each resource name has a global
   symbol associated with it. This global symbol has the form
   XtNresource name. For example, the symbol for ``foreground'' is
   XtNforeground. For further information, see the X Toolkit
   Intrinsics - C Language Interface.

   Argument are specified by using the following structure:



typedef struct {
        String name;
        XtArgVal value;
} Arg, *ArgList;

   The first approach is to statically initialize the argument
   list. For example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) 300},
};

   This approach is convenient for lists that do not need to be
   computed at runtime and makes adding or deleting new elements
   easy. The XtNumber macro is used to compute the number of
   elements in the argument list, preventing simple programming
   errors:

XtCreateWidget(name, class, parent, arglist, XtNumber(arglist));

   The second approach is to use the XtSetArg macro. For example:



Arg arglist[10];
XtSetArg(arglist[1], XtNwidth, 400);
XtSetArg(arglist[2], XtNheight, 300);

   To make it easier to insert and delete entries, you also can
   use a variable index:



Arg arglist[10];
Cardinal i=0;
XtSetArg(arglist[i], XtNwidth,  400);       i++;
XtSetArg(arglist[i], XtNheight, 300);       i++;

   The i variable can then be used as the argument list count in
   the widget create function. In this example, XtNumber would
   return 10, not 2, and therefore is not useful. You should not
   use auto-increment or auto-decrement within the first argument
   to XtSetArg . As it is currently implemented, XtSetArg is a
   macro that dereferences the first argument twice.

   The third approach is to individually set the elements of the
   argument list array:



Arg arglist[10];
arglist[0].name  = XtNwidth;
arglist[0].value = (XtArgVal) 400;
arglist[1].name  = XtNheight;
arglist[1].value = (XtArgVal) 300;

   Note that in this example, as in the previous example, XtNumber
   would return 10, not 2, and therefore would not be useful.

   The fourth approach is to use a mixture of the first and third
   approaches: you can statically define the argument list but
   modify some entries at runtime. For example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) NULL},
};
arglist[1].value = (XtArgVal) 300;

   In this example, XtNumber can be used, as in the first
   approach, for easier code maintenance.

Example Programs

   The best way to understand how to use any programming library
   is by trying some simple examples. A collection of example
   programs that introduces each of the widgets in that Athena
   widget set, as well as many important toolkit programming
   concepts, is available in the X11R5 contrib release as
   distributed by the X Consortium. It can be found in the
   directory contrib/examples/Xaw in the archive at
   http://www.x.org/releases/X11R5/contrib-1.tar.Z See the README
   file from that directory for a guide to the examples.

Chapter 3. Simple Widgets

   Table of Contents

   Command Widget

        Resources
        Command Actions

   Grip Widget

        Resources
        Grip Actions

   Label Widget

        Resources

   List Widget

        Resources
        List Actions
        List Callbacks
        Changing the List
        Highlighting an Item
        Unhighlighting an Item
        Retrieving the Currently Selected Item
        Restrictions

   Panner Widget

        Resources
        Panner Actions
        Panner Callbacks

   Repeater Widget

        Resources
        Repeater Actions

   Scrollbar Widget

        Resources
        Scrollbar Actions
        Scrollbar Callbacks
        Convenience Routines
        Setting Float Resources

   Simple Widget

        Resources

   StripChart Widget

        Resources
        Getting the StripChart Value

   Toggle Widget

        Resources
        Toggle Actions
        Toggle Actions
        Radio Groups
        Convenience Routines

   Each of these widgets performs a specific user interface
   function. They are simple because they cannot have widget
   children\(emthey may only be used as leaves of the widget tree.
   These widgets display information or take user input.

   Command

   A push button that, when selected, may cause a specific action
   to take place. This widget can display a multi-line string or a
   bitmap or pixmap image.

   Grip

   A rectangle that, when selected, will cause an action to take
   place.

   Label

   A rectangle that can display a multi-line string or a bitmap or
   pixmap image.

   List

   A list of text strings presented in row column format that may
   be individually selected. When an element is selected an action
   may take place.

   Panner

   A rectangular area containing a slider that may be moved in two
   dimensions. Notification of movement may be continuous or
   discrete.

   Repeater

   A push button that triggers an action at an increasing rate
   when selected. This widget can display a multi-line string or a
   bitmap or pixmap image.

   Scrollbar

   A rectangular area containing a thumb that when slid along one
   dimension may cause a specific action to take place. The
   Scrollbar may be oriented horizontally or vertically.

   Simple

   The base class for most of the simple widgets. Provides a
   rectangular area with a settable mouse cursor and special
   border.

   StripChart

   A real time data graph that will automatically update and
   scroll.

   Toggle

   A push button that contains state information. Toggles may also
   be used as "radio buttons" to implement a "one of many" or
   "zero or one of many" group of buttons. This widget can display
   a multi-line string or a bitmap or pixmap image.

Command Widget




Application header file <X11/Xaw/Command.h>

Class header file       <X11/Xaw/CommandP.h>

Class   commandWidgetClass

Class Name      Command

Superclass      Label


   The Command widget is an area, often rectangular, that contains
   text or a graphical image. Command widgets are often referred
   to as ``push buttons.'' When the pointer is over a Command
   widget, the widget becomes highlighted by drawing a rectangle
   around its perimeter. This highlighting indicates that the
   widget is ready for selection. When mouse button 1 is pressed,
   the Command widget indicates that it has been selected by
   reversing its foreground and background colors. When the mouse
   button is released, the Command widget's notify action is
   invoked, calling all functions on its callback list. If the
   pointer is moved off of the widget before the pointer button is
   released, the widget reverts to its normal foreground and
   background colors, and releasing the pointer button has no
   effect. This behavior allows the user to cancel an action.

Resources

   When creating a Command widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStyle ShapeStyle ShapeStyle   Rectangle
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0
   _

   \" Resource Descriptions

Command Actions

   The Command widget supports the following actions:
     * Switching the button's interior between the foreground and
       background colors with set, unset, and reset.
     * Processing application callbacks with notify
     * Switching the internal border between highlighted and
       unhighlighted states with highlight and unhighlight

   The following are the default translation bindings used by the
   Command widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  reset(\|)
        <Btn1Down>:     set(\|)
        <Btn1Up>:       notify(\|) unset(\|)

   The full list of actions supported by Command is:

   highlight(condition)

   Displays the internal highlight border in the color (foreground
   or background ) that contrasts with the interior color of the
   Command widget. The conditions WhenUnset and Always are
   understood by this action procedure. If no argument is passed,
   WhenUnset is assumed.

   unhighlight(\|)

   Displays the internal highlight border in the color (foreground
   or background ) that matches the interior color of the Command
   widget.

   set(\|)

   Enters the set state, in which notify is possible. This action
   causes the button to display its interior in the foreground
   color. The label or bitmap is displayed in the background
   color.

   unset(\|)

   Cancels the set state and displays the interior of the button
   in the background color. The label or bitmap is displayed in
   the foreground color.

   reset(\|)

   Cancels any set or highlight and displays the interior of the
   button in the background color, with the label or bitmap
   displayed in the foreground color.

   notify(\|)

   When the button is in the set state this action calls all
   functions in the callback list named by the callback resource.
   The value of the call_data argument passed to these functions
   is undefined.

   A very common alternative to registering callbacks is to
   augment a Command's translations with an action performing the
   desired function. This often takes the form of:



*Myapp*save.translations: #augment <Btn1Down>,<Btn1Up>: Save()

   When a bitmap of depth greater that one (1) is specified the
   set(), unset(), and reset() actions have no effect, since there
   are no foreground and background colors used in a multi-plane
   pixmap.

Grip Widget




Application header file <X11/Xaw/Grip.h>

Class header file       <X11/Xaw/GripP.h>

Class   gripWidgetClass

Class Name      Grip

Superclass      Simple


   The Grip widget provides a small rectangular region in which
   user input events (such as ButtonPress or ButtonRelease) may be
   handled. The most common use for the Grip widget is as an
   attachment point for visually repositioning an object, such as
   the pane border in a Paned widget.

Resources

   When creating a Grip widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   0
   callback Callback Callback   NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension   8
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension   8
   x Position Position   0
   y Position Position   0

   callback

   All routines on this list are called whenever the GripAction
   action routine is invoked. The call_data contains all
   information passed to the action routine. A detailed
   description is given below in the Grip Actions section.

   foreground

   A pixel value which indexes the widget's colormap to derive the
   color used to flood fill the entire Grip widget.

Grip Actions

   The Grip widget does not declare any default event translation
   bindings, but it does declare a single action routine named
   GripAction. The client specifies an arbitrary event translation
   table, optionally giving parameters to the GripAction routine.

   The GripAction routine executes the callbacks on the callback
   list, passing as call_data a pointer to a XawGripCallData
   structure, defined in the Grip widget's application header
   file.






typedef struct _XawGripCallData {
        XEvent *event;
        String *params;
        Cardinal num_params;
} XawGripCallDataRec, *XawGripCallData,
  GripCallDataRec, *GripCallData; /* supported for R4 compatibility */





   In this structure, the event is a pointer to the input event
   that triggered the action. params and num_params give the
   string parameters specified in the translation table for the
   particular event binding.

   The following is an example of a translation table that uses
   the GripAction:




        <Btn1Down>:     GripAction(press)
        <Btn1Motion>:   GripAction(move)
        <Btn1Up>:       GripAction(release)


   For a complete description of the format of translation tables,
   see the X Toolkit Intrinsics - C Language Interface.

Label Widget




Application header file <X11/Xaw/Label.h>

Class header file       <X11/Xaw/LabelP.h>

Class   labelWidgetClass

Class Name      Label

Superclass      Simple


   A Label widget holds a graphic displayed within a rectangular
   region of the screen. The graphic may be a text string
   containing multiple lines of characters in an 8 bit or 16 bit
   character set (to be displayed with a font), or in a multi-byte
   encoding (for use with a fontset). The graphic may also be a
   bitmap or pixmap. The Label widget will allow its graphic to be
   left, right, or center justified. Normally, this widget can be
   neither selected nor directly edited by the user. It is
   intended for use as an output device only.

Resources

   When creating a Label widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   See above
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

List Widget




Application header file <X11/Xaw/List.h>

Class header file       <X11/Xaw/ListP.h>

Class   listWidgetClass

Class Name      List

Superclass      Simple


   The List widget contains a list of strings formatted into rows
   and columns. When one of the strings is selected, it is
   highlighted, and the List widget's Notify action is invoked,
   calling all routines on its callback list. Only one string may
   be selected at a time.

Resources

   When creating a List widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback Callback   NULL
   colormap Colormap Colormap   Parent's Colormap
   columnSpacing Spacing Dimension   6
   cursor Cursor Cursor   XC_left_ptr
   cursorName Cursor String   NULL
   defaultColumns Columns int   2
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   font Font FontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   forceColumns Columns Boolean   False
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Enough space to contain the list
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   list List Pointer   name of widget
   longest Longest int A 0
   mappedWhenManaged MappedWhenManaged Boolean   True
   numberStrings NumberStrings int A computed for NULL terminated
   list
   pasteBuffer Boolean Boolean   False
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   rowSpacing Spacing Dimension   2
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   See below
   verticalList Boolean Boolean   False
   width Width Dimension A Enough space to contain the list
   x Position Position   0
   y Position Position   0
   _

   callback

   All functions on this list are called whenever the notify
   action is invoked. The call_data argument contains information
   about the element selected and is described in detail in the
   List Callbacks section.

   columnSpacing

   rowSpacing

   The amount of space, in pixels, between each of the rows and
   columns in the list.

   defaultColumns

   The default number of columns. This value is used when neither
   the width nor the height of the List widget is specified or
   when forceColumns is True.

   font

   The text font to use when displaying the list, when the
   international resource is false.

   fontSet

   The text font set to use when displaying the list, when the
   international resource is true.

   forceColumns

   Forces the default number of columns to be used regardless of
   the List widget's current size.

   foreground

   A pixel value which indexes the widget's colormap to derive the
   color used to paint the text of the list elements.

   \fPinternalHeight\fP

   \fPinternalWidth\fP

   The margin, in pixels, between the edges of the list and the
   corresponding edge of the List widget's window.

   list

   An array of text strings displayed in the List widget. If
   numberStrings is zero (the default) then the list must be NULL
   terminated. If a value is not specified for the list, then
   numberStrings is set to 1, and the name of the widget is used
   as the list, and longest is set to the length of the name of
   the widget. The list is used in place, and must be available to
   the List widget for the lifetime of this widget, or until it is
   changed with XtSetValues or XawListChange.

   longest

   Specifies the width, in pixels, of the longest string in the
   current list. The List widget will compute this value if zero
   (the default) is specified. If this resource is set by hand,
   entries longer than this will be clipped to fit.

   numberStrings

   The number of strings in the current list. If a value of zero
   (the default) is specified, the List widget will compute it.
   When computing the number of strings the List widget assumes
   that the list is NULL terminated.

   pasteBuffer

   If this resource is set to True then the name of the currently
   selected list element will be put into CUT_BUFFER_0.

   verticalList

   If this resource is set to True then the list elements will be
   presented in column major order.

List Actions

   The List widget supports the following actions:
     * Highlighting and unhighlighting the list element under the
       pointer with Set and Unset
     * Processing application callbacks with Notify

   The following is the default translation table used by the List
   Widget:



<Btn1Down>,<Btn1Up>:    Set(\|) Notify(\|)


   The full list of actions supported by List widget is:

   Set(\|)

   Sets the list element that is currently under the pointer. To
   inform the user that this element is currently set, it is drawn
   with foreground and background colors reversed. If this action
   is called when there is no list element under the cursor, the
   currently set element will be unset.

   Unset(\|)

   Cancels the set state of the element under the pointer, and
   redraws it with normal foreground and background colors.

   Notify(\|)

   Calls all callbacks on the List widget's callback list.
   Information about the currently selected list element is passed
   in the call_data argument (see List Callbacks below).

List Callbacks

   All procedures on the List widget's callback list will have a
   XawListReturnStruct passed to them as call_data. The structure
   is defined in the List widget's application header file.



typedef struct _XawListReturnStruct {
        String string;  /* string shown in the list. */
        int list_index; /* index of the item selected. */
} XawListReturnStruct;



Note

   The list_index item used to be called simply index.
   Unfortunately, this name collided with a global name defined on
   some operating systems, and had to be changed.

Changing the List

   To change the list that is displayed, use XawListChange .

   voidfsfunc XawListChange(Widget w, String* list, intnitems,
   longest, Boolean resize);

   w

   Specifies the List widget.

   list

   Specifies the new list for the List widget to display.

   nitems

   Specifies the number of items in the list. If a value less than
   1 is specified, list must be NULL terminated, and the number of
   items will be calculated by the List widget.

   longest

   Specifies the length of the longest item in the list in pixels.
   If a value less than 1 is specified, the List widget will
   calculate the value.

   resize

   Specifies a Boolean value that if True indicates that the List
   widget should try to resize itself after making the change. The
   constraints of the List widget's parent are always enforced,
   regardless of the value specified here.

   XawListChange will unset all list elements that are currently
   set before the list is actually changed. The list is used in
   place, and must remain usable for the lifetime of the List
   widget, or until list has been changed again with this function
   or with XtSetValues.

Highlighting an Item

   To highlight an item in the list, use XawListHighlight .

   voidfsfunc XawListHighlight(Widget w, int item);

   w

   Specifies the List widget.

   item

   Specifies an index into the current list that indicates the
   item to be highlighted.

   Only one item can be highlighted at a time. If an item is
   already highlighted when XawListHighlight is called, the
   highlighted item is unhighlighted before the new item is
   highlighted.

Unhighlighting an Item

   To unhighlight the currently highlighted item in the list, use
   XawListUnhighlight .

   voidfsfunc XawListUnhighlight(Widget w);

   w

   Specifies the List widget.

Retrieving the Currently Selected Item

   To retrieve the list element that is currently set, use
   XawListShowCurrent .

   XawListReturnStructfsfunc *XawListShowCurrent(Widget w);

   w

   Specifies the List widget.

   XawListShowCurrent returns a pointer to an XawListReturnStruct
   structure, containing the currently highlighted item. If the
   value of the index member is XAW_LIST_NONE, the string member
   is undefined, and no item is currently selected.

Restrictions

   Many programmers create a ``scrolled list'' by putting a List
   widget with many entries as a child of a Viewport widget. The
   List continues to create a window as big as its contents, but
   that big window is only visible where it intersects the parent
   Viewport's window. (I.e., it is ``clipped.'')

   While this is a useful technique, there is a serious drawback.
   X does not support windows above 32,767 pixels in width or
   height, but this height limit will be exceeded by a List's
   window when the List has many entries (i.e., with a 12 point
   font, about 3000 entries would be too many.)

Panner Widget




Application header file <X11/Xaw/Panner.h>

Class header file       <X11/Xaw/PannerP.h>

Class           pannerWidgetClass

Class Name      Panner

Superclass      Simple


   A Panner widget is a rectangle, called the ``canvas,'' on which
   another rectangle, the ``slider,'' moves in two dimensions. It
   is often used with a Porthole widget to move, or ``scroll,'' a
   third widget in two dimensions, in which case the slider's size
   and position gives feedback as to what portion of the third
   widget is visible.

   The slider may be scrolled around the canvas by pressing,
   dragging, and releasing Button1; the default translation also
   enables scrolling via arrow keys and some other keys. While
   scrolling is in progress, the application receives notification
   through callback procedures. Notification may be done either
   continuously whenever the slider moves or discretely whenever
   the slider has been given a new location.

Resources

   When creating a Panner widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   allowOff AllowOff Boolean   False
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   backgroundStipple BackgroundStipple String   NULL
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   canvasHeight CanvasHeight Dimension   0
   canvasWidth CanvasWidth Dimension   0
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   defaultScale DefaultScale Dimension   8
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A depends on orientation
   internalSpace InternalSpace Dimension   4
   international International Boolean C False
   lineWidth LineWidth Dimension   0
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   reportCallback ReportCallback Callback   NULL
   resize Resize Boolean   True
   rubberBand RubberBand Boolean   False
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shadowColor ShadowColor Pixel   XtDefaultForeground
   shadowThickness ShadowThickness Dimension   2
   sliderX SliderX Position   0
   sliderY SliderY Position   0
   sliderHeight SliderHeight Dimension   0
   sliderWidth SliderWidth Dimension   0
   translations Translations TranslationTable   See below
   width Width Dimension A depends on orientation
   x Position Position   0
   y Position Position   0

   allowOff

   Whether to allow the edges of the slider to go off the edges of
   the canvas.

   backgroundStipple

   The name of a bitmap pattern to be used as the background for
   the area representing the canvas.

   canvasHeight

   canvasWidth

   The size of the canvas.

   defaultScale

   The percentage size that the Panner widget should have relative
   to the size of the canvas.

   foreground

   A pixel value which indexes the widget's colormap to derive the
   color used to draw the slider.

   internalSpace

   The width of internal border in pixels between a slider
   representing the full size of the canvas and the edge of the
   Panner widget.

   lineWidth

   The width of the lines in the rubberbanding rectangle when
   rubberbanding is in effect instead of continuous scrolling. The
   default is 0.

   reportCallback

   All functions on this callback list are called when the notify
   action is invoked. See the Panner Actions section for details.

   resize

   Whether or not to resize the panner whenever the canvas size is
   changed so that the defaultScale is maintained.

   rubberBand

   Whether or not scrolling should be discrete (only moving a
   rubberbanded rectangle until the scrolling is done) or
   continuous (moving the slider itself). This controls whether or
   not the move action procedure also invokes the notify action
   procedure.

   shadowColor

   The color of the shadow underneath the slider.

   shadowThickness

   The width of the shadow underneath the slider.

   sliderX

   sliderY

   The location of the slider in the coordinates of the canvas.

   sliderHeight

   sliderWidth

   The size of the slider.

Panner Actions

   The actions supported by the Panner widget are:

   start()

   This action begins movement of the slider.

   stop()

   This action ends movement of the slider.

   abort()

   This action ends movement of the slider and restores it to the
   position it held when the start action was invoked.

   move()

   This action moves the outline of the slider (if the rubberBand
   resource is True) or the slider itself (by invoking the notify
   action procedure).

   page(xamount,yamount)

   This action moves the slider by the specified amounts. The
   format for the amounts is a signed or unsigned floating-point
   number (e.g., +1.0 or \-.5) followed by either p indicating
   pages (slider sizes), or c indicating canvas sizes. Thus,
   page(+0,+.5p) represents vertical movement down one-half the
   height of the slider and page(0,0) represents moving to the
   upper left corner of the canvas.

   notify()

   This action informs the application of the slider's current
   position by invoking the reportCallback functions registered by
   the application.

   set(what,value)

   This action changes the behavior of the Panner. The what
   argument must currently be the string rubberband and controls
   the value of the rubberBand resource. The value argument may
   have one of the values on, off, or toggle.

   The default bindings for Panner are:


        <Btn1Down>:     start(\|)
        <Btn1Motion>:   move(\|)
        <Btn1Up>:       notify(\|) stop(\|)
        <Btn2Down>:     abort(\|)
        <Key>KP_Enter:  set(rubberband,toggle)
        <Key>space:     page(+1p,+1p)
        <Key>Delete:    page(\-1p,\-1p)
        <Key>BackSpace: page(\-1p,\-1p)
        <Key>Left:      page(\-.5p,+0)
        <Key>Right:     page(+.5p,+0)
        <Key>Up:        page(+0,\-.5p)
        <Key>Down:      page(+0,+.5p)
        <Key>Home:      page(0,0)

Panner Callbacks

   The functions registered on the reportCallback list are invoked
   by the notify action as follows:

   voidfsfunc ReportProc(Widget panner, XtPointer client_data,
   XtPointer report);

   panner

   Specifies the Panner widget.

   panner

   Specifies the client data.

   panner

   Specifies a pointer to an XawPannerReport structure containing
   the location and size of the slider and the size of the canvas.

Repeater Widget




Application header file <X11/Xaw/Repeater.h>

Class header file       <X11/Xaw/RepeaterP.h>

Class   repeaterWidgetClass

Class Name      Repeater

Superclass      Command


   The Repeater widget is a subclass of the Command widget; see
   the Command documentation for details. The difference is that
   the Repeater can call its registered callbacks repeatedly, at
   an increasing rate. The default translation does so for the
   duration the user holds down pointer button 1 while the pointer
   is on the Repeater.

Resources

   When creating a Repeater widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   decay Decay Int   5
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   flash Boolean Boolean   False
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   initialDelay Delay Int   200
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   minimumDelay MinimumDelay Int   10
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   repeatDelay Delay Int   50
   resize Resize Boolean   True
   screen Screen Pointer R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStyle ShapeStyle ShapeStyle   Rectangle
   startCallback StartCallback Callback   NULL
   stopCallback StopCallback Callback   NULL
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

   \" Resource Descriptions

   decay

   The number of milliseconds that should be subtracted from each
   succeeding interval while the Repeater button is being held
   down until the interval has reached minimumDelay milliseconds.

   flash

   Whether or not to flash the Repeater button whenever the timer
   goes off.

   initialDelay

   The number of milliseconds between the beginning of the
   Repeater button being held down and the first invocation of the
   callback function.

   minimumDelay

   The minimum time between callbacks in milliseconds.

   repeatDelay

   The number of milliseconds between each callback after the
   first (minus an increasing number of decays).

   startCallback

   The list of functions to invoke by the start action (typically
   when the Repeater button is first pressed). The callback data
   parameter is set to NULL.

   stopCallback

   The list of functions to invoke by the stop action (typically
   when the Repeater button is released). The callback data
   parameter is set to NULL.

Repeater Actions

   The Repeater widget supports the following actions beyond those
   of the Command button:

   start()

   This invokes the functions on the startCallback and callback
   lists and sets a timer to go off in initialDelay milliseconds.
   The timer will cause the callback functions to be invoked with
   increasing frequency until the stop action occurs.

   stop()

   This invokes the functions on the stopCallback list and
   prevents any further timers from occuring until the next start
   action.

   The following are the default translation bindings used by the
   Repeater widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  unhighlight(\|)
        <Btn1Down>:     set(\|) start(\|)
        <Btn1Up>:       stop(\|) unset(\|)

Scrollbar Widget

Application header file     <X11/Xaw/Scrollbar.h>
Class header file           <X11/Xaw/ScrollbarP.h>
Class                       scrollbarWidgetClass
Class Name                  Scrollbar
Superclass                  Simple

   A Scrollbar widget is a rectangle, called the ``canvas,'' on
   which another rectangle, the ``thumb,'' moves in one dimension,
   either vertically or horizontally. A Scrollbar can be used
   alone, as a value generator, or it can be used within a
   composite widget (for example, a Viewport). When a Scrollbar is
   used to move, or ``scroll,'' the contents of another widget,
   the size and the position of the thumb usually give feedback as
   to what portion of the other widget's contents are visible.

   Each pointer button invokes a specific action. Pointer buttons
   1 and 3 do not move the thumb automatically. Instead, they
   return the pixel position of the cursor on the scroll region.
   When pointer button 2 is clicked, the thumb moves to the
   current pointer position. When pointer button 2 is held down
   and the pointer is moved, the thumb follows the pointer.

   The pointer cursor in the scroll region changes depending on
   the current action. When no pointer button is pressed, the
   cursor appears as a double-headed arrow that points in the
   direction that scrolling can occur. When pointer button 1 or 3
   is pressed, the cursor appears as a single-headed arrow that
   points in the logical direction that the thumb will move. When
   pointer button 2 is pressed, the cursor appears as an arrow
   that points to the top or the left of the thumb.

   When the user scrolls, the application receives notification
   through callback procedures. For both discrete scrolling
   actions, the callback returns the Scrollbar widget, the
   client_data, and the pixel position of the pointer when the
   button was released. For continuous scrolling, the callback
   routine returns the scroll bar widget, the client data, and the
   current relative position of the thumb. When the thumb is moved
   using pointer button 2, the callback procedure is invoked
   continuously. When either button 1 or 3 is pressed, the
   callback procedure is invoked only when the button is released
   and the client callback procedure is responsible for moving the
   thumb.

Resources

   When creating a Scrollbar widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A depends on orientation
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   jumpProc Callback XtCallbackList   NULL
   length Length Dimension   1
   mappedWhenManaged MappedWhenManaged Boolean   True
   minimumThumb MinimumThumb Dimension   7
   orientation Orientation Orientation   XtorientVertical
   (vertical)
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R parent's Screen
   scrollDCursor Cursor Cursor   XC_sb_down_arrow
   scrollHCursor Cursor Cursor   XC_sb_h_double_arrow
   scrollLCursor Cursor Cursor   XC_sb_left_arrow
   scrollProc Callback XtCallbackList   NULL
   scrollRCursor Cursor Cursor   XC_sb_right_arrow
   scrollUCursor Cursor Cursor   XC_sb_up_arrow
   scrollVCursor Cursor Cursor   XC_sb_v_arrow
   sensitive Sensitive Boolean   True
   shown Shown Float   0.0
   thickness Thickness Dimension   14
   thumb Thumb Bitmap   GreyPixmap
   thumbProc Callback XtCallbackList   NULL
   topOfThumb TopOfThumb Float   0.0
   translations Translations TranslationTable   See below
   width Width Dimension A depends on orientation
   x Position Position   0
   y Position Position   0

   foreground

   A pixel value which indexes the widget's colormap to derive the
   color used to draw the thumb.

   jumpProc

   All functions on this callback list are called when the
   NotifyThumb action is invoked. See the Scrollbar Actions
   section for details.

   length

   The height of a vertical scrollbar or the width of a horizontal
   scrollbar.

   minimumThumb

   The smallest size, in pixels, to which the thumb can shrink.

   orientation

   The orientation is the direction that the thumb will be allowed
   to move. This value can be either XtorientVertical or
   XtorientHorizontal.

   scrollDCursor

   This cursor is used when scrolling backward in a vertical
   scrollbar.

   scrollHCursor

   This cursor is used when a horizontal scrollbar is inactive.

   scrollLCursor

   This cursor is used when scrolling forward in a horizontal
   scrollbar.

   scrollProc

   All functions on this callback list may be called when the
   NotifyScroll action is invoked. See the \fBScrollbar Actions\fP
   section for details.

   scrollRCursor

   This cursor is used when scrolling backward in a horizontal
   scrollbar, or when thumbing a vertical scrollbar.

   scrollUCursor

   This cursor is used when scrolling forward in a vertical
   scrollbar, or when thumbing a horizontal scrollbar.

   scrollVCursor

   This cursor is used when a vertical scrollbar is inactive.

   shown

   This is the size of the thumb, expressed as a percentage (0.0 -
   1.0) of the length of the scrollbar.

   thickness

   The width of a vertical scrollbar or the height of a horizontal
   scrollbar.

   thumb

   This pixmap is used to tile (or stipple) the thumb of the
   scrollbar. If no tiling is desired, then set this resource to
   None. This resource will accept either a bitmap or a pixmap
   that is the same depth as the window. The resource converter
   for this resource constructs bitmaps from the contents of
   files. (See Converting Bitmaps for details.)

   topOfThumb

   The location of the top of the thumb, as a percentage (0.0 -
   1.0) of the length of the scrollbar. This resource was called
   top in previous versions of the Athena widget set. The name
   collided with the a Form widget constraint resource, and had to
   be changed.

Scrollbar Actions

   The actions supported by the Scrollbar widget are:

   StartScroll(value)

   The possible values are Forward, Backward, or Continuous. This
   must be the first action to begin a new movement.

   NotifyScroll(value)

   The possible values are Proportional or FullLength. If the
   argument to StartScroll was Forward or Backward, NotifyScroll
   executes the scrollProc callbacks and passes either; the
   position of the pointer, if value is Proportional, or the full
   length of the scroll bar, if value is FullLength. If the
   argument to StartScroll was Continuous, NotifyScroll returns
   without executing any callbacks.

   EndScroll(\^)

   This must be the last action after a movement is complete.

   MoveThumb(\^)

   Repositions the Scrollbar's thumb to the current pointer
   location.

   NotifyThumb(\^)\

   Calls the callbacks and passes the relative position of the
   pointer as a percentage of the scroll bar length.

   The default bindings for Scrollbar are:
     <Btn1Down>:     StartScroll(Forward)
     <Btn2Down>:     StartScroll(Continuous) MoveThumb(\|) NotifyThumb(\
|)
     <Btn3Down>:     StartScroll(Backward)
     <Btn2Motion>:     MoveThumb(\|) NotifyThumb(\|)
     <BtnUp>:     NotifyScroll(Proportional) EndScroll(\|)

   Examples of additional bindings a user might wish to specify in
   a resource file are:
*Scrollbar.Translations: \\
     ~Meta<Key>space:     StartScroll(Forward) NotifyScroll(FullLength)
\\n\\
      Meta<Key>space:     StartScroll(Backward) NotifyScroll(FullLength)
 \\n\\
          EndScroll(\|)

Scrollbar Callbacks

   There are two callback lists provided by the Scrollbar widget.
   The procedural interface for these functions is described here.

   The calling interface to the scrollProc callback procedure is:

   voidfsfunc ScrollProc(Widget scrollbar, XtPointer client_data,
   XtPointer position);

   scrollbar

   Specifies the Scrollbar widget.

   client_data

   Specifies the client data.

   position

   Specifies a pixel position in integer form.

   The scrollProc callback is used for incremental scrolling and
   is called by the NotifyScroll action. The position argument is
   a signed quantity and should be cast to an int when used. Using
   the default button bindings, button 1 returns a positive value,
   and button 3 returns a negative value. In both cases, the
   magnitude of the value is the distance of the pointer in pixels
   from the top (or left) of the Scrollbar. The value will never
   be greater than the length of the Scrollbar.

   The calling interface to the jumpProc callback procedure is:

   voidfsfunc JumpProc(Widget scrollbar, XtPointer client_data,
   XtPointer percent_ptr);

   scrollbar

   Specifies the ID of the scroll bar widget.

   client_data

   Specifies the client data.

   percent_ptr

   Specifies the floating point position of the thumb (0.0 \-
   1.0).

   The jumpProc callback is used to implement smooth scrolling and
   is called by the NotifyThumb action. Percent_ptr must be cast
   to a pointer to float before use; i.e.
     float percent = *(float*)percent_ptr;

   With the default button bindings, button 2 moves the thumb
   interactively, and the jumpProc is called on each new position
   of the pointer, while the pointer button remains down. The
   value specified by percent_ptr is the current location of the
   thumb (from the top or left of the Scrollbar) expressed as a
   percentage of the length of the Scrollbar.

Convenience Routines

   To set the position and length of a Scrollbar thumb, use

   voidfsfunc XawScrollbarSetThumb(Widget w, float top, float
   shown);

   w

   Specifies the Scrollbar widget.

   top

   Specifies the position of the top of the thumb as a fraction of
   the length of the Scrollbar.

   shown

   Specifies the length of the thumb as a fraction of the total
   length of the Scrollbar.

   XawScrollbarThumb moves the visible thumb to a new position
   (0.0 \- 1.0) and length (0.0 \- 1.0). Either the top or shown
   arguments can be specified as \-1.0, in which case the current
   value is left unchanged. Values greater than 1.0 are truncated
   to 1.0.

   If called from jumpProc, XawScrollbarSetThumb has no effect.

Setting Float Resources

   The shown and topOfThumb resources are of type float. These
   resources can be difficult to get into an argument list. The
   reason is that C performs an automatic cast of the float value
   to an integer value, usually truncating the important
   information. The following code fragment is one portable method
   of getting a float into an argument list.
     top = 0.5;
     if (sizeof(float) > sizeof(XtArgVal)) {
     /*
     \ * If a float is larger than an XtArgVal then pass this
     \ * resource value by reference.
     \ */
          XtSetArg(args[0], XtNshown, &top);
     }
     else {
     /*
     \ * Convince C not to perform an automatic conversion, which
     \ * would truncate 0.5 to 0.
     \ */
          XtArgVal * l_top = (XtArgVal *) &top;
          XtSetArg(args[0], XtNshown, *l_top);
     }

Simple Widget




Application Header file <Xaw/Simple.h>

Class Header file       <Xaw/SimpleP.h>

Class           simpleWidgetClass

Class Name      Simple

Superclass      Core


   The Simple widget is not very useful by itself, as it has no
   semantics of its own. It main purpose is to be used as a common
   superclass for the other simple Athena widgets. This widget
   adds six resources to the resource list provided by the Core
   widget and its superclasses.

Resources

   When creating a Simple widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension   0
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension   0
   x Position Position   0
   y Position Position   0

StripChart Widget




Application Header file <Xaw/StripChart.h>

Class Header file       <Xaw/StripCharP.h>

Class           stripChartWidgetClass

Class Name      StripChart

Superclass      Simple


   The StripChart widget is used to provide a roughly real time
   graphical chart of a single value. For example, it is used by
   the common client program xload to provide a graph of processor
   load. The StripChart reads data from an application, and
   updates the chart at the update interval specified.

Resources

   When creating a StripChart widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   getValue Callback XtCallbackList   NULL
   height Height Dimension   120
   highlight Foreground Pixel   XtDefaultForeground
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   jumpScroll JumpScroll int A half the width of the widget
   mappedWhenManaged MappedWhenManaged Boolean   True
   minScale Scale int   1
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Pointer R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   update Interval int   10
   width Width Dimension   120
   x Position Position   0
   y Position Position   0

   foreground

   A pixel value which indexes the widget's colormap to derive the
   color that will be used to draw the graph.

   getValue

   A list of callback functions to call every update seconds. This
   list should contain one function, which returns the value to be
   graphed by the StripChart widget. The following section
   describes the procedural interface. Behavior when this list has
   more than one function is undefined.

   highlight

   A pixel value which indexes the widget's colormap to derive the
   color that will be used to draw the scale lines on the graph.

   jumpScroll

   When the graph reaches the right edge of the window it must be
   scrolled to the left. This resource specifies the number of
   pixels it will jump. Smooth scrolling can be achieved by
   setting this resource to 1.

   minScale

   The minimum scale for the graph. The number of divisions on the
   graph will always be greater than or equal to this value.

   update

   The number of seconds between graph updates. Each update is
   represented on the graph as a 1 pixel wide line. Every update
   seconds the getValue procedure will be used to get a new graph
   point, and this point will be added to the right end of the
   StripChart.

Getting the StripChart Value

   The StripChart widget will call the application routine passed
   to it as the getValue callback function every update seconds to
   obtain another point for the StripChart graph.

   The calling interface for the getValue callback is:

   fsfunc void(*getValueProc)(Widget w, XtPointer client_data,
   XtPointer value);

   w

   Specifies the StripChart widget.

   client_data

   Specifies the client data.

   value

   Returns a pointer to a double. The application should set the
   address pointed to by this argument to a double containing the
   value to be graphed on the StripChart.

   This function is used by the StripChart to call an application
   routine. The routine will pass the value to be graphed back to
   the the StripChart in the value field of this routine.

Toggle Widget

Application Header file     <Xaw/Toggle.h>
Class Header file     <Xaw/ToggleP.h>
Class          toggleWidgetClass
Class Name     Toggle
Superclass      Command

   The Toggle widget is an area, often rectangular, that displays
   a graphic. The graphic may be a text string containing multiple
   lines of characters in an 8 bit or 16 bit character set (to be
   displayed with a font), or in a multi-byte encoding (for use
   with a fontset). The graphic may also be a bitmap or pixmap.

   This widget maintains a Boolean state (e.g. True/False or
   On/Off) and changes state whenever it is selected. When the
   pointer is on the Toggle widget, the Toggle widget may become
   highlighted by drawing a rectangle around its perimeter. This
   highlighting indicates that the Toggle widget is ready for
   selection. When pointer button 1 is pressed and released, the
   Toggle widget indicates that it has changed state by reversing
   its foreground and background colors, and its notify action is
   invoked, calling all functions on its callback list. If the
   pointer is moved off of the widget before the pointer button is
   released, the Toggle widget reverts to its previous foreground
   and background colors, and releasing the pointer button has no
   effect. This behavior allows the user to cancel the operation.

   Toggle widgets may also be part of a ``radio group.'' A radio
   group is a list of at least two Toggle widgets in which no more
   than one Toggle may be set at any time. A radio group is
   identified by the widget ID of any one of its members. The
   convenience routine XawToggleGetCurrent will return information
   about the Toggle widget in the radio group.

   Toggle widget state is preserved across changes in sensitivity.

Resources

   When creating a Toggle widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   radioData RadioData Pointer   Name of widget
   radioGroup Widget Widget   No radio group
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStype ShapeStyle ShapeStyle   Rectangle
   state State Boolean   Off
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

   radioData

   Specifies the data that will be returned by XawToggleGetCurrent
   when this is the currently set widget in the radio group. This
   value is also used to identify the Toggle that will be set by a
   call to XawToggleSetCurrent. The value NULL will be returned by
   XawToggleGetCurrent if no widget in a radio group is currently
   set. Programmers must not specify NULL (or Zero) as radioData.

   radioGroup

   Specifies another Toggle widget that is in the radio group to
   which this Toggle widget should be added. A radio group is a
   group of at least two Toggle widgets, only one of which may be
   set at a time. If this value is NULL (the default) then the
   Toggle will not be part of any radio group and can change state
   without affecting any other Toggle widgets. If the widget
   specified in this resource is not already in a radio group then
   a new radio group will be created containing these two Toggle
   widgets. No Toggle widget can be in multiple radio groups. The
   behavior of a radio group of one toggle is undefined. A
   converter is registered which will convert widget names to
   widgets without caching.

   state

   Specifies whether the Toggle widget is set (True) or unset
   (False).

Toggle Actions

   The Toggle widget supports the following actions:
     * Switching the Toggle widget between the foreground and
       background colors with set and unset and toggle
     * Processing application callbacks with notify
     * Switching the internal border between highlighted and
       unhighlighted states with highlight and unhighlight

   The following are the default translation bindings used by the
   Toggle widget:
     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     toggle() notify()

Toggle Actions

   The full list of actions supported by Toggle is:

   highlight(condition)

   Displays the internal highlight border in the color (foreground
   or background ) that contrasts with the interior color of the
   Toggle widget. The conditions WhenUnset and Always are
   understood by this action procedure. If no argument is passed
   then WhenUnset is assumed.

   unhighlight()

   Displays the internal highlight border in the color (foreground
   or background ) that matches the interior color of the Toggle
   widget.

   set()

   Enters the set state, in which notify is possible. This action
   causes the Toggle widget to display its interior in the
   foreground color. The label or bitmap is displayed in the
   background color.

   unset()

   Cancels the set state and displays the interior of the Toggle
   widget in the background color. The label or bitmap is
   displayed in the foreground color.

   toggle()

   Changes the current state of the Toggle widget, causing to be
   set if it was previously unset, and unset if it was previously
   set. If the widget is to be set, and is in a radio group then
   this procedure may unset another Toggle widget causing all
   routines on its callback list to be invoked. The callback
   routines for the Toggle that is to be unset will be called
   before the one that is to be set.

   reset()

   Cancels any set or highlight and displays the interior of the
   Toggle widget in the background color, with the label displayed
   in the foreground color.

   notify()

   When the Toggle widget is in the set state this action calls
   all functions in the callback list named by the callback
   resource. The value of the call_data argument in these callback
   functions is undefined.

   When a bitmap of depth greater that one (1) is specified the
   set(), unset(), and reset() actions have no effect, since there
   are no foreground and background colors used in a multi-plane
   pixmap.

Radio Groups

   There are typically two types of radio groups desired by
   applications. The default translations for the Toggle widget
   implement a "zero or one of many" radio group. This means that
   there may be no more than one Toggle widget active, but there
   need not be any Toggle widgets active.

   The other type of radio group is "one of many" and has the more
   strict policy that there will always be exactly one radio
   button active. Toggle widgets can be used to provide this
   interface with a slight modification to the translation table
   of each Toggle in the group.
     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     set() notify()

   This translation table will not allow any Toggle to be unset
   except as a result of another Toggle becoming set. It is the
   application programmer's responsibility to choose an initial
   state for the radio group by setting the state resource of one
   of its member widgets to True.

Convenience Routines

   The following functions allow easy access to the Toggle
   widget's radio group functionality.

Changing the Toggle's Radio Group.

   To enable an application to change the Toggle's radio group,
   add the Toggle to a radio group, or remove the Toggle from a
   radio group, use XawToggleChangeRadioGroup.

   voidfsfunc XawToggleChangeRadioGroup(Widgetw, radio_group);

   w

   Specifies the Toggle widget.

   radio_group

   Specifies any Toggle in the new radio group. If NULL then the
   Toggle will be removed from any radio group of which it is a
   member.

   If a Toggle is already set in the new radio group, and the
   Toggle to be added is also set then the previously set Toggle
   in the radio group is unset and its callback procedures are
   invoked. Finding the Currently selected Toggle in a radio group
   of Toggles

   To find the currently selected Toggle in a radio group of
   Toggle widgets use XawToggleGetCurrent.

   XtPointerfsfunc XawToggleGetCurrent(XtPointer
   XawToggleGetCurrent(radio_group), Widget radio_group);

   radio_group

   Specifies any Toggle widget in the radio group.

   The value returned by this function is the radioData of the
   Toggle in this radio group that is currently set. The default
   value for radioData is the name of that Toggle widget. If no
   Toggle is set in the radio group specified then NULL is
   returned. Changing the Toggle that is set in a radio group.

   To change the Toggle that is currently set in a radio group use
   XawToggleSetCurrent.

   voidfsfunc
   XawToggleSetCurrent(voidXawToggleSetCurrent(radio_group,
   radio_data), Widget radio_group, XtPointer radio_data);

   radio_group

   Specifies any Toggle widget in the radio group.

   radio_data

   Specifies the radioData identifying the Toggle that should be
   set in the radio group specified by the radio_group argument.

   XawToggleSetCurrent locates the Toggle widget to be set by
   matching radio_data against the radioData for each Toggle in
   the radio group. If none match, XawToggleSetCurrent returns
   without making any changes. If more than one Toggle matches,
   XawToggleSetCurrent will choose a Toggle to set arbitrarily. If
   this causes any Toggle widgets to change state, all routines in
   their callback lists will be invoked. The callback routines for
   a Toggle that is to be unset will be called before the one that
   is to be set. Unsetting all Toggles in a radio group.

   To unset all Toggle widgets in a radio group use
   XawToggleUnsetCurrent.

   voidfsfunc XawToggleUnsetCurrent(void
   XawToggleUnsetCurrent(radio_group), Widget radio_group);

   radio_group

   Specifies any Toggle widget in the radio group.

   If this causes a Toggle widget to change state, all routines on
   its callback list will be invoked.

Chapter 4. Menus

   Table of Contents

   Using the Menus
   Sme Object

        Resources
        Subclassing the Sme Object

   SmeBSB Object

        Resources

   SmeLine Object

        Resources

   The Athena widget set provides support for single paned
   non-hierarchical popup and pulldown menus. Since menus are such
   a common user interface tool, support for them must be provided
   in even the most basic widget sets. In menuing as in other
   areas, the Athena Widget Set provides only basic functionality.

   Menus in the Athena widget set are implemented as a menu
   container (the SimpleMenu widget) and a collection of objects
   that comprise the menu entries. The SimpleMenu widget is itself
   a direct subclass of the OverrideShell widget class, so no
   other shell is necessary when creating a menu. The managed
   children of a SimpleMenu must be subclasses of the Sme (Simple
   Menu Entry) object.

   The Athena widget set provides three classes of Sme objects
   that may be used to build menus.

   Sme

   The base class of all menu entries. It may be used as a menu
   entry itself to provide blank space in a menu. "Sme" means
   "Simple Menu Entry."

   SmeBSB

   This menu entry provides a selectable entry containing a text
   string. A bitmap may also be placed in the left and right
   margins. "BSB" means "Bitmap String Bitmap."

   SmeLine

   This menu entry provides an unselectable entry containing a
   separator line.

   The SimpleMenu widget informs the window manager that it should
   ignore its window by setting the Override Redirect flag. This
   is the correct behavior for the press-drag-release style of
   menu operation. If click-move-click or "pinable" menus are
   desired it is the responsibility of the application programmer,
   using the SimpleMenu resources, to inform the window manager of
   the menu.

   To allow easy creation of pulldown menus, a MenuButton widget
   is also provided as part of the Athena widget set.

Using the Menus

   The default configuration for the menus is press-drag-release.
   The menus will typically be activated by clicking a pointer
   button while the pointer is over a MenuButton, causing the menu
   to appear in a fixed location relative to that button; this is
   a pulldown menu. Menus may also be activated when a specific
   pointer and/or key sequence is used anywhere in the
   application; this is a popup menu (e.g. clicking Ctrl-<pointer
   button 1> in the common application xterm). In this case the
   menu should be positioned under the cursor. Typically menus
   will be placed so the pointer cursor is on the first menu
   entry, or the last entry selected by the user.

   The menu remains on the screen as long as the pointer button is
   held down. Moving the pointer will highlight different menu
   items. If the pointer leaves the menu, or moves over an entry
   that cannot be selected then no menu entry will highlighted.
   When the desired menu entry has been highlighted, releasing the
   pointer button removes the menu, and causes any mechanism
   associated with this entry to be invoked.

Sme Object



Application Header file <X11/Xaw/Sme.h>

Class Header file       <X11/Xaw/SmeP.h>

Class           smeObjectClass

Class Name      Sme

Superclass      RectObj

   The Sme object is the base class for all menu entries. While
   this object is mainly intended to be subclassed, it may be used
   in a menu to add blank space between menu entries.

Resources

   The resources associated with the SmeLine object are defined in
   this section, and affect only the single menu entry specified
   by this object. There are no new resources added for this
   class, as it picks up all its resources from the RectObj class.
        Name              Class            Type      Notes Default Value
  ancestorSensitive AncestorSensitive    Boolean               True
      callback          Callback      XtCallbackList           NULL
   destroyCallback      Callback      XtCallbackList           NULL
       height            Height         Dimension                0
    international     International      Boolean       C       False
      sensitive         Sensitive        Boolean               True
        width             Width         Dimension                1

   Keep in mind that the SimpleMenu widget will force all menu
   items to be the width of the widest entry.

Subclassing the Sme Object

   To Create a new Sme object class you will need to define three
   class methods. These methods allow the SimpleMenu to highlight
   and unhighlight the menu entry as the pointer cursor moves over
   it, as well as notify the entry when the user has selected it.
   All of these methods may be inherited from the Sme object,
   although the default semantics are not very interesting.

   Highlight(\|)

   Called to put the menu entry into the highlighted state.

   Unhighlight(\|)

   Called to return the widget to its normal (unhighlighted)
   state.

   Notify(\|)

   Called when the user selects this menu entry.

   Other then these methods, creating a new object is straight
   forward. Here is some information that may help you avoid some
   common mistakes.
    1. Objects can be zero pixels high.
    2. Objects draw on their parent's window, therefore the
       Drawing dimensions are different from those of widgets. For
       instance, y locations vary from y to y + height, not 0 to
       height.
    3. XtSetValues calls may come from the application while the
       Sme is highlighted, and if the SetValues method returns
       True, will result in an expose event. The SimpleMenu may
       later call the menu entry's unhighlight procedure. However,
       due to the asynchronous nature of X, the expose event
       generated by XtSetValues will come after this unhighlight.
    4. Remember that your subclass of the Sme does not own the
       window. Share the space with other menu entries, and
       refrain from drawing outside the subclass's own section of
       the menu.

SmeBSB Object




Application Header file <X11/Xaw/SmeBSB.h>

Class Header file       <X11/Xaw/SmeBSBP.h>

Class           smeBSBObjectClass

Class Name      SmeBSB

Superclass      Sme


   The SmeBSB object is used to create a menu entry that contains
   a string, and optional bitmaps in its left and right margins.
   Since each menu entry is an independent object, the application
   is able to change the font, color, height, and other attributes
   of the menu entries, on an entry by entry basis. The format of
   the string may either be the encoding of the 8 bit font
   utilized, or in a multi-byte encoding for use with a fontSet.

Resources

   The resources associated with the SmeBSB object are defined in
   this section, and affect only the single menu entry specified
   by this object.
   Name Class Type Notes Default Value
   ancestorSensitive AncestorSensitive Boolean D True
   callback Callback Callback   NULL
   destroyCallback Callback XtCallbackList   NULL
   font Font FontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Font height + vertSpace
   international International Boolean C False
   justify Justify Justify   XtjustifyLeft
   label Label String   NULL
   leftBitmap LeftBitmap Pixmap   XtUnspecifiedPixmap
   leftMargin leftMargin Dimension   4
   rightBitmap RightBitmap Pixmap   XtUnspecifiedPixmap
   rightMargin rightMargin Dimension   4
   sensitive Sensitive Boolean   True
   vertSpace VertSpace int   25
   width Width Dimension A TextWidth + margins

   callback

   All callback functions on this list are called when the
   SimpleMenu notifies this entry that the user has selected it.

   font

   The text font to use when displaying the label, when the
   international resource is false.

   fontSet

   The text font set to use when displaying the label, when the
   international resource is true.

   foreground

   A pixel value which indexes the SimpleMenu's colormap to derive
   the foreground color of the menu entry's window. This color is
   also used to render all 1's in the left and right bitmaps. Keep
   in mind that the SimpleMenu widget will force the width of all
   menu entries to be the width of the longest entry.

   justify

   How the label is to be rendered between the left and right
   margins when the space is wider than the actual text. This
   resource may be specified with the values XtJustifyLeft,
   XtJustifyCenter, or XtJustifyRight. When specifying the
   justification from a resource file the values left, center, or
   right may be used.

   label

   This is a the string that will be displayed in the menu entry.
   The exact location of this string within the bounds of the menu
   entry is controlled by the leftMargin, rightMargin, vertSpace,
   and justify resources.

   leftBitmap

   rightBitmap

   This is a name of a bitmap to display in the left or right
   margin of the menu entry. All 1's in the bitmap will be
   rendered in the foreground color, and all 0's will be drawn in
   the background color of the SimpleMenu widget. It is the
   programmers' responsibility to make sure that the menu entry is
   tall enough, and the appropriate margin wide enough to accept
   the bitmap. If care is not taken the bitmap may extend into
   another menu entry, or into this entry's label.

   leftMargin

   rightMargin

   This is the amount of space (in pixels) that will be left
   between the edge of the menu entry and the label string.

   vertSpace

   This is the amount of vertical padding, expressed as a
   percentage of the height of the font, that is to be placed
   around the label of a menu entry.. The label and bitmaps are
   always centered vertically within the menu. The default value
   for this resource (25) causes the default height to be 125% of
   the height of the font.

SmeLine Object



Application Header file <X11/Xaw/SmeLine.h>

Class Header file       <X11/Xaw/SmeLineP.h>

Class           smeLineObjectClass

Class Name      SmeLine

Superclass      Sme

   The SmeLine object is used to add a horizontal line or menu
   separator to a menu. Since each SmeLine is an independent
   object, the application is able to change the color, height,
   and other attributes of the SmeLine objects on an entry by
   entry basis. This object is not selectable, and will not
   highlight when the pointer cursor is over it.

Resources

   The resources associated with the SmeLine object are defined in
   this section, and affect only the single menu entry specified
   by this object.
       Name           Class          Type      Notes    Default Value
  destroyCallback   Callback    XtCallbackList              NULL
    foreground     Foreground       Pixel            XtDefaultForeground
      height         Height       Dimension               lineWidth
   international  International    Boolean       C          False
     lineWidth      LineWidth     Dimension                   1
      stipple        Stipple        Pixmap           XtUnspecifiedPixmap
       width          Width       Dimension                   1

   foreground

   A pixel value which indexes the SimpleMenu's colormap to derive
   the foreground color used to draw the separator line. Keep in
   mind that the SimpleMenu widget will force all menu items to be
   the width of the widest entry. Thus, setting the width is
   generally not very important.

   lineWidth

   The width of the horizontal line that is to be displayed.

   stipple

   If a bitmap is specified for this resource, the line will be
   stippled through it. This allows the menu separator to be
   rendered as something more exciting than just a line. For
   instance, if you define a stipple that is a chain link, then
   your menu separators will look like chains.

Chapter 5. Text Widgets

   Table of Contents

   Text Widget for Users

        Default Key Bindings
        Search and Replace
        File Insertion
        Text Selections for Users

   Text Widget Actions

        Cursor Movement Actions\fP
        Delete Actions
        Selection Actions
        The New Line Actions
        Kill and Actions
        Miscellaneous Actions
        Text Selections for Application Programmers

   Default Translation Bindings
   Text Functions

        Selecting Text
        Unhighlighting Text
        Getting Current Text Selection
        Replacing Text
        Searching for Text
        Redisplaying Text
        Resources Convenience Routines

   Customizing the Text Widget
   Text Widget

        Resources

   TextSink Object

        Resources
        Subclassing the TextSink

   TextSrc Object

        Resources
        Subclassing the TextSrc

   Ascii Sink Object and Multi Sink Object

        Resources

   Ascii Source Object and Multi Source Object

        Resources
        Convenience Routines

   Ascii Text Widget

        Resources

   The Text widget provides a window that will allow an
   application to display and edit one or more lines of text.
   Options are provided to allow the user to add Scrollbars to its
   window, search for a specific string, and modify the text in
   the buffer.

   The Text widget is made up of a number of pieces; it was
   modularized to ease customization. The AsciiText widget class
   (actually not limited to ASCII but so named for compatibility)
   is be general enough to most needs. If more flexibility,
   special features, or extra functionality is needed, they can be
   added by implementing a new TextSource or TextSink, or by
   subclassing the Text Widget (See Section 5.8 for customization
   details.)

   The words insertion point are used in this chapter to refer to
   the text caret. This is the symbol that is displayed between
   two characters in the file. The insertion point marks the
   location where any new characters will be added to the file. To
   avoid confusion the pointer cursor will always be referred to
   as the pointer.

   The text widget supports three edit modes, controlling the
   types of modifications a user is allowed to make:

     * Append-only
     * Editable
     * Read-only

   Read-only mode does not allow the user or the programmer to
   modify the text in the widget. While the entire string may be
   reset in read-only mode with XtSetValues, it cannot be modified
   via with XawTextReplace. Append-only and editable modes allow
   the text at the insertion point to be modified. The only
   difference is that text may only be added to or removed from
   the end of a buffer in append-only mode.

Text Widget for Users

   The Text widget provides many of the common keyboard editing
   commands. These commands allow users to move around and edit
   the buffer. If an illegal operation is attempted, (such as
   deleting characters in a read-only text widget), the X server
   will beep.

Default Key Bindings

   The default key bindings are patterned after those in the EMACS
   text editor:


Ctrl-a  Beginning Of Line       Meta-b  Backward Word
Ctrl-b  Backward Character      Meta-f  Forward Word
Ctrl-d  Delete Next Character   Meta-i  Insert File
Ctrl-e  End Of Line     Meta-k  Kill To End Of Paragraph
Ctrl-f  Forward Character       Meta-q  Form Paragraph
Ctrl-g  Multiply Reset  Meta-v  Previous Page
Ctrl-h  Delete Previous Character       Meta-y  Insert Current Selection
Ctrl-j  Newline And Indent      Meta-z  Scroll One Line Down
Ctrl-k  Kill To End Of Line     Meta-d  Delete Next Word
Ctrl-l  Redraw Display  Meta-D  Kill Word
Ctrl-m  Newline Meta-h  Delete Previous Word
Ctrl-n  Next Line       Meta-H  Backward Kill Word
Ctrl-o  Newline And Backup      Meta-<  Beginning Of File
Ctrl-p  Previous Line   Meta->  End Of File
Ctrl-r  Search/Replace Backward Meta-]  Forward Paragraph
Ctrl-s  Search/Replace Forward  Meta-[  Backward Paragraph
Ctrl-t  Transpose Characters
Ctrl-u  Multiply by 4   Meta-Delete     Delete Previous Word
Ctrl-v  Next Page       Meta-Shift Delete       Kill Previous Word
Ctrl-w  Kill Selection  Meta-Backspace  Delete Previous Word
Ctrl-y  Unkill  Meta-Shift Backspace    Kill Previous Word
Ctrl-z  Scroll One Line Up
Ctrl-\\ Reconnect to input method
Kanji   Reconnect to input method

   In addition, the pointer may be used to cut and paste text:



        Button 1 Down   Start Selection
        Button 1 Motion Adjust Selection
        Button 1 Up     End Selection (cut)

        Button 2 Down   Insert Current Selection (paste)

        Button 3 Down   Extend Current Selection
        Button 3 Motion Adjust Selection
        Button 3 Up     End Selection (cut)


   Since all of these key and pointer bindings are set through the
   translations and resource manager, the user and the application
   programmer can modify them by changing the Text widget's
   translations resource.

Search and Replace

   The Text widget provides a search popup that can be used to
   search for a string within the current Text widget. The popup
   can be activated by typing either Control-r or Control-s. If
   Control-s is used the search will be forward in the file from
   the current location of the insertion point; if Control-r is
   used the search will be backward. The activated popup is placed
   under the pointer. It has a number of buttons that allow both
   text searches and text replacements to be performed.

   At the top of the search popup are two toggle buttons labeled
   backward and forward. One of these buttons will always be
   highlighted; this is the direction in which the search will be
   performed. The user can change the direction at any time by
   clicking on the appropriate button.

   Directly under the buttons there are two text areas, one
   labeled Search for: and the other labeled Replace with:. If
   this is a read-only Text widget the Replace with: field will be
   insensitive and no replacements will be allowed. After each of
   these labels will be a text field. This field will allow the
   user to enter a string to search for and the string to replace
   it with. Only one of these text fields will have a window
   border around it; this is the active text field. Any key
   presses that occur when the focus in in the search popup will
   be directed to the active text field. There are also a few
   special key sequences:


Carriage Return:        Execute the action, and pop down the search widg
et.
Tab:    Execute the action, then move to the next field.
Shift Carriage Return:  Execute the action, then move to the next field.
Control-q Tab:  Enter a Tab into a text field.
Control-c:      Pop down the search popup.

   Using these special key sequences should allow simple searches
   without ever removing one's hands from the keyboard.

   Near the bottom of the search popup is a row of buttons. These
   buttons allow the same actions to to be performed as the key
   sequences, but the buttons will leave the popup active. This
   can be quite useful if many searches are being performed, as
   the popup will be left on the display. Since the search popup
   is a transient window, it may be picked up with the window
   manager and pulled off to the side for use at a later time.

   Search

   Search for the specified string.

   Replace

   Replace the currently highlighted string with the string in the
   Replace with text field, and move onto the next occurrence of
   the Search for text field. The functionality is commonly
   referred to as query-replace.

   ReplaceAll

   Replace all occurrences of the search string with the replace
   string from the current insertion point position to the end (or
   beginning) of the file. There is no key sequence to perform
   this action.

   ReplaceAll

   Remove the search popup from the screen.

   Finally, when international resource is true, there may be a
   pre-edit buffer below the button row, for composing input. Its
   presence is determined by the X locale in use and the
   VendorShell's preeditType resource.

   The widget hierarchy for the search popup is show below, all
   widgets are listed by class and instance name.
Text  <name of Text widget>
        TransientShell  search
                Form  form
                        Label label1
                        Label  label2
                        Toggle  backwards
                        Toggle  forwards
                        Label  searchLabel
                        Text  searchText
                        Label  replaceLabel
                        Text  replaceText
                        Command  search
                        Command  replaceOne
                        Command  replaceAll
                        Command  cancel

File Insertion

   To insert a file into a text widget, type the key sequence
   Meta-i, which will activate the file insert popup. This popup
   will appear under the pointer, and any text typed while the
   focus is in this popup will be redirected to the text field
   used for the filename. When the desired filename has been
   entered, click on Insert File, or type Carriage Return. The
   named file will then be inserted in the text widget beginning
   at the insertion point position. If an error occurs when
   opening the file, an error message will be printed, prompting
   the user to enter the filename again. The file insert may be
   aborted by clicking on Cancel. If Meta-i is typed at a text
   widget that is read-only, it will beep, as no file insertion is
   allowed.

   The widget hierarchy for the file insert popup is show below;
   all widgets are listed by class and instance name.
Text  <name of Text widget>
        TransientShell  insertFile
                Form  form
                        Label  label
                        Text  text
                        Command  insert
                        Command  cancel

Text Selections for Users

   The text widgets have a text selection mechanism that allows
   the user to copy pieces of the text into the PRIMARY selection,
   and paste into the text widget some text that another
   application (or text widget) has put in the PRIMARY selection.

   One method of selecting text is to press pointer button 1 on
   the beginning of the text to be selected, drag the pointer
   until all of the desired text is highlighted, and then release
   the button to activate the selection. Another method is to
   click pointer button 1 at one end of the text to be selected,
   then click pointer button 3 at the other end.

   To modify a currently active selection, press pointer button 3
   near either the end of the selection that you want to adjust.
   This end of the selection may be moved while holding down
   pointer button 3. When the proper area has been highlighted
   release the pointer button to activate the selection.

   The selected text may now be pasted into another application,
   and will remain active until some other client makes a
   selection. To paste text that some other application has put
   into the PRIMARY selection use pointer button 2. First place
   the insertion point where you would like the text to be
   inserted, then click and release pointer button 2.

   Rapidly clicking pointer button 1 the following number of times
   will adjust the selection as described.

   Two

   Select the word under the pointer. A word boundary is defined
   by the Text widget to be a Space, Tab, or Carriage Return.

   Three

   Select the line under the pointer.

   Four

   Select the paragraph under the pointer. A paragraph boundary is
   defined by the text widget as two Carriage Returns in a row
   with only Spaces or Tabs between them.

   Five

   Select the entire text buffer.

   To unset the text selection, click pointer button 1 without
   moving it.

Text Widget Actions

   All editing functions are performed by translation manager
   actions that may be specified through the translations resource
   in the Text widget.



Insert Point Movement     Delete
     forward-character         delete-next-character
     backward-character        delete-previous-character
     forward-word              delete-next-word
     backward-word             delete-previous-word
     forward-paragraph         delete-selection
     backward-paragraph
     beginning-of-line
     end-of-line          Selection
     next-line                 select-word
     previous-line             select-all
     next-page                 select-start
     previous-page             select-adjust
     beginning-of-file         select-end
     end-of-file               extend-start
     scroll-one-line-up        extend-adjust
     scroll-one-line-down      extend-end
                               insert-selection


Miscellaneous             New Line
     redraw-display            newline-and-indent
     insert-file               newline-and-backup
     insert-char               newline
     insert-string
     display-caret
     focus-in             Kill
     focus-in                  kill-word
     search                    backward-kill-word
     multiply                  kill-selection
     form-paragraph            kill-to-end-of-line
     transpose-characters      kill-paragraph
     no-op                     kill-to-end-of-paragraph
     XawWMProtocols
     reconnect-im

   Most of the actions take no arguments, and unless otherwise
   noted you may assume this to be the case.

Cursor Movement Actions\fP

   forward-character()

   backward-character()

   These actions move the insert point forward or backward one
   character in the buffer. If the insert point is at the end or
   beginning of a line this action will move the insert point to
   the next (or previous) line.

   forward-word()

   backward-word()

   These actions move the insert point to the next or previous
   word boundary. A word boundary is defined as a Space, Tab or
   Carriage Return.

   forward-paragraph()

   backward-paragraph()

   These actions move the insert point to the next or previous
   paragraph boundary. A paragraph boundary is defined as two
   Carriage Returns in a row with only Spaces or Tabs between
   them.

   beginning-of-line()

   end-of-line()

   These actions move to the beginning or end of the current line.
   If the insert point is already at the end or beginning of the
   line then no action is taken.

   next-line()

   previous-line()

   These actions move the insert point up or down one line. If the
   insert point is currently N characters from the beginning of
   the line then it will be N characters from the beginning of the
   next or previous line. If N is past the end of the line, the
   insert point is placed at the end of the line.

   next-page()

   previous-page()

   These actions move the insert point up or down one page in the
   file. One page is defined as the current height of the text
   widget. The insert point is always placed at the first
   character of the top line by this action.

   beginning-of-file()

   end-of-file()

   These actions place the insert point at the beginning or end of
   the current text buffer. The text widget is then scrolled the
   minimum amount necessary to make the new insert point location
   visible.

   scroll-one-line-up()

   scroll-one-line-down()

   These actions scroll the current text field up or down by one
   line. They do not move the insert point. Other than the
   scrollbars this is the only way that the insert point may be
   moved off of the visible text area. The widget will be scrolled
   so that the insert point is back on the screen as soon as some
   other action is executed.

Delete Actions

   delete-next-character()

   delete-previous-character()

   These actions remove the character immediately before or after
   the insert point. If a Carriage Return is removed then the next
   line is appended to the end of the current line.

   delete-next-word()

   delete-previous-word()

   These actions remove all characters between the insert point
   location and the next word boundary. A word boundary is defined
   as a Space, Tab or Carriage Return.

   delete-selection()

   This action removes all characters in the current selection.
   The selection can be set with the selection actions.

Selection Actions

   select-word()

   This action selects the word in which the insert point is
   currently located. If the insert point is between words then it
   will select the previous word.

   select-all()

   This action selects the entire text buffer.

   select-start()

   This action sets the insert point to the current pointer
   location (if triggered by a button event) or text cursor
   location (if triggered by a key event). It will then begin a
   selection at this location. If many of these selection actions
   occur quickly in succession then the selection count mechanism
   will be invoked (see the section titled \fBText Selections for
   Application Programmers\fP for details).

   select-adjust()

   This action allows a selection started with the select-start
   action to be modified, as described above.

   select-end(name[,name,...])

   This action ends a text selection that began with the
   select-start action, and asserts ownership of the selection or
   selections specified. A name can be a selection (e.g., PRIMARY)
   or a cut buffer (e.g., CUT_BUFFER0). Note that case is
   important. If no names are specified, PRIMARY is asserted.

   extend-start()

   This action finds the nearest end of the current selection, and
   moves it to the current pointer location (if triggered by a
   button event) or text cursor location (if triggered by a key
   event).

   extend-adjust()

   This action allows a selection started with an extend-start
   action to be modified.

   extend-end(name[,name,...])

   This action ends a text selection that began with the
   extend-start action, and asserts ownership of the selection or
   selections specified. A name can be a selection (e.g. PRIMARY)
   or a cut buffer (e.g CUT_BUFFER0). Note that case is important.
   If no names are given, PRIMARY is asserted.

   insert-selection(name[,name,...])

   This action retrieves the value of the first (left-most) named
   selection that exists or the cut buffer that is not empty and
   inserts it into the Text widget at the current insert point
   location. A name can be a selection (e.g. PRIMARY) or a cut
   buffer (e.g CUT_BUFFER0). Note that case is important.

The New Line Actions

   newline-and-indent()

   This action inserts a newline into the text and adds spaces to
   that line to indent it to match the previous line.

   newline-and-backup()

   This action inserts a newline into the text after the insert
   point.

   newline()

   This action inserts a newline into the text before the insert
   point.

Kill and Actions

   kill-word()

   backward-kill-word()

   These actions act exactly like the delete-next-word and
   delete-previous-word actions, but they stuff the word that was
   killed into the kill buffer (CUT_BUFFER_1).

   kill-selection()

   This action deletes the current selection and stuffs the
   deleted text into the kill buffer (CUT_BUFFER_1).

   kill-to-end-of-line()

   This action deletes the entire line to the right of the insert
   point position, and stuffs the deleted text into the kill
   buffer (CUT_BUFFER_1).

   kill-paragraph()

   This action deletes the current paragraph, if between
   paragraphs it deletes the paragraph above the insert point, and
   stuffs the deleted text into the kill buffer (CUT_BUFFER_1).

   kill-to-end-of-paragraph()

   This action deletes everything between the current insert point
   location and the next paragraph boundary, and stuffs the
   deleted text into the kill buffer (CUT_BUFFER_1).

Miscellaneous Actions

   redraw-display()

   This action recomputes the location of all the text lines on
   the display, scrolls the text to vertically center the line
   containing the insert point on the screen, clears the entire
   screen, and redisplays it.

   insert-file([filename])

   This action activates the insert file popup. The filename
   option specifies the default filename to put in the filename
   buffer of the popup. If no filename is specified the buffer is
   empty at startup.

   insert-char()

   This action may only be attached to a key event. When the
   international resource is false, this action calls
   XLookupString to translate the event into a (rebindable)
   Latin-1 character (sequence) and inserts it into the text at
   the insert point. When the international resource is true,
   characters are passed to the input method via XwcLookupString,
   and any committed string returned is inserted into the text at
   the insert point.

   insert-string(string[,string,...])

   This action inserts each string into the text at the insert
   point location. Any string beginning with the characters "0x"
   followed by an even number of hexadecimal digits is interpreted
   as a hexadecimal constant and the corresponding string is
   inserted instead. This hexadecimal string may represent up to
   50 8-bit characters. When theinternational resource is true, a
   hexadecimal string is intrepeted as being in a multi-byte
   encoding, and a hexadecimal or regular string will result in an
   error message if it is not legal in the current locale.

   display-caret(state,when)

   This action allows the insert point to be turned on and off.
   The state argument specifies the desired state of the insert
   point. This value may be any of the string values accepted for
   Boolean resources (e.g. on, True, off, False, etc.). If no
   arguments are specified, the default value is True. The when
   argument specifies, for EnterNotify or LeaveNotify events
   whether or not the focus field in the event is to be examined.
   If the second argument is not specified, or specified as
   something other than always then if the action is bound to an
   EnterNotify or LeaveNotify event, the action will be taken only
   if the focus field is True. An augmented binding that might be
   useful is:



     *Text.Translations: #override \\
          <FocusIn>:     display-caret(on) \\n\\
          <FocusOut>:     display-caret(off)

   focus-in()

   focus-out()

   These actions do not currently do anything.

   search(direction,[string])

   This action activates the search popup. The direction must be
   specified as either forward or backward. The string is optional
   and is used as an initial value for the Search for: string. For
   further explanation of the search widget see the section on
   Text Searches.

   multiply(value)

   The multiply action allows the user to multiply the effects of
   many of the text actions. Thus the following action sequence
   multiply(10) delete-next-word() will delete 10 words. It does
   not matter whether these actions take place in one event or
   many events. Using the default translations the key sequence
   \fIControl-u, Control-d\fP will delete 4 characters. Multiply
   actions can be chained, thus \fImultiply(5) multiply(5)\fP is
   the same as multiply(25). If the string reset is passed to the
   multiply action the effects of all previous multiplies are
   removed and a beep is sent to the display.

   form-paragraph()

   This action removes all the Carriage Returns from the current
   paragraph and reinserts them so that each line is as long as
   possible, while still fitting on the current screen. Lines are
   broken at word boundaries if at all possible. This action
   currently works only on Text widgets that use ASCII text.

   transpose-characters()

   This action will swap the position of the character to the left
   of the insert point with the character to the right of the
   insert point. The insert point will then be advanced one
   character.

   no-op([action])

   The no-op action makes no change to the text widget, and is
   mainly used to override translations. This action takes one
   optional argument. If this argument is RingBell then a beep is
   sent to the display.

   XawWMProtocols([wm_protocol_name])

   This action is written specifically for the file insertion and
   the search and replace dialog boxes. This action is attached to
   those shells by the Text widget, in order to handle
   ClientMessage events with the WM_PROTOCOLS atom in the detail
   field. This action supports WM_DELETE_WINDOW on the Text widget
   popups, and may support other window manager protocols if
   necessary in the future. The popup will be dismissed if the
   window manager sends a WM_DELETE_WINDOW request and there are
   no parameters in the action call, which is the default. The
   popup will also be dismissed if the parameters include the
   string ``wm_delete_window,'' and the event is a ClientMessage
   event requesting dismissal or is not a ClientMessage event.
   This action is not sensitive to the case of the strings passed
   as parameters.

   reconnect-im()

   When the international resource is true, input is usually
   passed to an input method, a separate process, for composing.
   Sometimes the connection to this process gets severed; this
   action will attempt to reconnect it. Causes for severage
   include network trouble, and the user explicitly killing one
   input method and starting a new one. This action may also
   establish first connection when the application is started
   before the input method.

Text Selections for Application Programmers

   The default behavior of the text selection array is described
   in the section called Text Selections for Users. To modify the
   selections a programmer must construct a XawTextSelectType
   array (called the selection array), containing the selections
   desired, and pass this as the new value for the selectionTypes
   resource. The selection array may also be modified using the
   XawTextSetSelectionArray function. All selection arrays must
   end with the value XawselectNull. The selectionTypes resource
   has no converter registered and cannot be modified through the
   resource manager.

   The array contains a list of entries that will be called when
   the user attempts to select text in rapid succession with the
   select-start action (usually by clicking a pointer button). The
   first entry in the selection array will be used when the
   select-start action is initially called. The next entry will be
   used when select-start is called again, and so on. If a timeout
   value (1/10 of a second) is exceeded, the the next select-start
   action will begin at the top of the selection array. When
   XawselectNull is reached the array is recycled beginning with
   the first element.
   XawselectAll Selects the contents of the entire buffer.
   XawselectChar Selects text characters as the pointer moves over
   them.
   XawselectLine Selects the entire line.
   XawselectNull Indicates the end of the selection array.
   XawselectParagraph Selects the entire paragraph.
   XawselectPosition Selects the current pointer position.
   XawselectWord Selects whole words as the pointer moves onto
   them.

   The default selectType array is:

{XawselectPosition, XawselectWord, XawselectLine, XawselectParagraph, Xa
wselectAll, XawselectNull}

   The selection array is not copied by the text widgets. The
   application must allocate space for the array and cannot
   deallocate or change it until the text widget is destroyed or
   until a new selection array is set.

Default Translation Bindings

   The following translations are defaults built into every Text
   widget. They can be overridden, or replaced by specifying a new
   value for the Text widget's translations resource.



     Ctrl<Key>A:     beginning-of-line() \\n\\
     Ctrl<Key>B:     backward-character() \\n\\
     Ctrl<Key>D:     delete-next-character() \\n\\
     Ctrl<Key>E:     end-of-line() \\n\\
     Ctrl<Key>F:     forward-character() \\n\\
     Ctrl<Key>G:     multiply(Reset) \\n\\
     Ctrl<Key>H:     delete-previous-character() \\n\\
     Ctrl<Key>J:     newline-and-indent() \\n\\
     Ctrl<Key>K:     kill-to-end-of-line() \\n\\
     Ctrl<Key>L:     redraw-display() \\n\\
     Ctrl<Key>M:     newline() \\n\\
     Ctrl<Key>N:     next-line() \\n\\
     Ctrl<Key>O:     newline-and-backup() \\n\\
     Ctrl<Key>P:     previous-line() \\n\\
     Ctrl<Key>R:     search(backward) \\n\\
     Ctrl<Key>S:     search(forward) \\n\\
     Ctrl<Key>T:     transpose-characters() \\n\\
     Ctrl<Key>U:     multiply(4) \\n\\
     Ctrl<Key>V:     next-page() \\n\\
     Ctrl<Key>W:     kill-selection() \\n\\
     Ctrl<Key>Y:     insert-selection(CUT_BUFFER1) \\n\\
     Ctrl<Key>Z:     scroll-one-line-up() \\n\\
     Ctrl<Key>\\:     reconnect-im() \\n\\
     Meta<Key>B:     backward-word() \\n\\
     Meta<Key>F:     forward-word() \\n\\
     Meta<Key>I:     insert-file() \\n\\
     Meta<Key>K:     kill-to-end-of-paragraph() \\n\\
     Meta<Key>Q:     form-paragraph() \\n\\
     Meta<Key>V:     previous-page() \\n\\
     Meta<Key>Y:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     Meta<Key>Z:     scroll-one-line-down() \\n\\
     :Meta<Key>d:     delete-next-word() \\n\\
     :Meta<Key>D:     kill-word() \\n\\
     :Meta<Key>h:     delete-previous-word() \\n\\
     :Meta<Key>H:     backward-kill-word() \\n\\
     :Meta<Key>\\<:     beginning-of-file() \\n\\
     :Meta<Key>\\>:     end-of-file() \\n\\
     :Meta<Key>]:     forward-paragraph() \\n\\
     :Meta<Key>[:     backward-paragraph() \\n\\
     ~Shift Meta<Key>Delete:          delete-previous-word() \\n\\
     \ Shift Meta<Key>Delete:          backward-kill-word() \\n\\
     ~Shift Meta<Key>Backspace:     delete-previous-word() \\n\\
     \ Shift Meta<Key>Backspace:     backward-kill-word() \\n\\
     <Key>Right:     forward-character() \\n\\
     <Key>Left:     backward-character() \\n\\
     <Key>Down:     next-line() \\n\\
     <Key>Up:     previous-line() \\n\\
     <Key>Delete:     delete-previous-character() \\n\\
     <Key>BackSpace:     delete-previous-character() \\n\\
     <Key>Linefeed:     newline-and-indent() \\n\\
     <Key>Return:     newline() \\n\\
     <Key>:          insert-char() \\n\\
     <Key>Kanji:     reconnect-im() \\n\\
     <FocusIn>:     focus-in() \\n\\
     <FocusOut>:     focus-out() \\n\\
     <Btn1Down>:     select-start() \\n\\
     <Btn1Motion>:     extend-adjust() \\n\\
     <Btn1Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn2Down>:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn3Down>:     extend-start() \\n\\
     <Btn3Motion>:     extend-adjust() \\n\\
     <Btn3Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n

Text Functions

   The following functions are provided as convenience routines
   for use with the Text widget. Although many of these actions
   can be performed by modifying resources, these interfaces are
   frequently more efficient.

   These data structures are defined in the Text widget's public
   header file, <X11/Xaw/Text.h>.

   typedef long XawTextPosition;

   Character positions in the Text widget begin at 0 and end at n,
   where n is the number of characters in the Text source widget.



typedef struct {
        int firstPos;
        int length;
        char *ptr;
        unsigned long format;
} XawTextBlock, *XawTextBlockPtr;

   firstPos

   The first position, or index, to use within the ptr field. The
   value is commonly zero.

   length

   The number of characters to be used from the ptr field. The
   number of characters used is commonly the number of characters
   in ptr, and must not be greater than the length of the string
   in ptr.

   ptr

   Contains the string to be referenced by the Text widget.

   format

   This flag indicates whether the data pointed to by ptr is char
   or wchar_t. When the associated widget has international set to
   false this field must be XawFmt8Bit. When the associated widget
   has international set to true this field must be either
   XawFmt8Bit or XawFmtWide.

Note

   Note: Previous versions of Xaw used FMT8BIT , which has been
   retained for backwards compatibility. FMT8BIT is deprecated and
   will eventually be removed from the implementation.

Selecting Text

   To select a piece of text, use XawTextSetSelection :

   voidfsfunc XawTextSetSelection(Widget w, XawTextPositionleft,
   right);

   w

   Specifies the Text widget.

   left

   Specifies the character position at which the selection begins.

   right

   Specifies the character position at which the selection ends.

   See section 5.4 for a description of XawTextPosition. If
   redisplay is enabled, this function highlights the text and
   makes it the PRIMARY selection. This function does not have any
   effect on CUT_BUFFER0.

Unhighlighting Text

   To unhighlight previously highlighted text in a widget, use
   XawTextUnsetSelection:

   voidfsfunc XawTextUnsetSelection(Widget w);

   w

   Specifies the Text widget.

Getting Current Text Selection

   To retrieve the text that has been selected by this text widget
   use XawTextGetSelectionPos:

   voidfsfunc XawTextGetSelectionPos(Widget w,
   XawTextPosition*begin_return, *end_return);

   w

   Specifies the Text widget.

   begin_return

   Returns the beginning of the text selection.

   end_return

   Returns the end of the text selection.

   See section 5.4 for a description of XawTextPosition. If the
   returned values are equal, no text is currently selected.

Replacing Text

   To modify the text in an editable Text widget use
   XawTextReplace:

   intfsfunc XawTextReplace(Widget w, XawTextPositionstart, end,
   XawTextBlock *text);

   w

   Specifies the Text widget.

   start

   Specifies the starting character position of the text
   replacement.

   end

   Specifies the ending character position of the text
   replacement.

   text

   Specifies the text to be inserted into the file.

   This function will not be able to replace text in read-only
   text widgets. It will also only be able to append text to an
   append-only text widget.

   See section 5.4 for a description of XawTextPosition and
   XawTextBlock.

   This function may return the following values:

   XawEditDone

   The text replacement was successful.

   XawPositionError

   The edit mode is XawtextAppend and start is not the position of
   the last character of the source.

   XawEditError

   Either the Source was read-only or the range to be deleted is
   larger than the length of the Source.

   The XawTextReplace arguments start and end represent the text
   source character positions for the existing text that is to be
   replaced by the text in the text block. The characters from
   start up to but not including end are deleted, and the
   characters specified on the text block are inserted in their
   place. If start and end are equal, no text is deleted and the
   new text is inserted after start.

Searching for Text

   To search for a string in the Text widget, use XawTextSearch:

   XawTextPositionfsfunc XawTextSearch(Widget w,
   XawTextScanDirection dir, XawTextBlock* text);

   w

   Specifies the Text widget.

   dir

   Specifies the direction to search in. Legal values are
   XawsdLeft and XawsdRight.

   text

   Specifies a text block structure that contains the text to
   search for.

   See section 5.4 for a description of XawTextPosition and
   XawTextBlock. The XawTextSearch function will begin at the
   insertion point and search in the direction specified for a
   string that matches the one passed in text. If the string is
   found the location of the first character in the string is
   returned. If the string could not be found then the value
   XawTextSearchError is returned.

Redisplaying Text

   To redisplay a range of characters, use XawTextInvalidate:

   voidfsfunc XawTextInvalidate(Widget w, XawTextPositionfrom,
   to);

   w

   Specifies the Text widget.

   from

   Specifies the start of the text to redisplay.

   to

   Specifies the end of the text to redisplay.

   See section 5.4 for a description of XawTextPosition. The
   XawTextInvalidate function causes the specified range of
   characters to be redisplayed immediately if redisplay is
   enabled or the next time that redisplay is enabled.

   To enable redisplay, use XawTextEnableRedisplay:

   voidfsfunc XawTextEnableRedisplay(Widget w);

   w

   Specifies the Text widget.

   The XawTextEnableRedisplay function flushes any changes due to
   batched updates when XawTextDisableRedisplay was called and
   allows future changes to be reflected immediately.

   To disable redisplay while making several changes, use
   XawTextDisableRedisplay.

   voidfsfunc XawTextDisableRedisplay(Widget w);

   w

   Specifies the Text widget.

   The XawTextDisableRedisplay function causes all changes to be
   batched until either XawTextDisplay or XawTextEnableRedisplay
   is called.

   To display batched updates, use XawTextDisplay:

   voidfsfunc XawTextDisplay(Widget w);

   w

   Specifies the Text widget.

   The XawTextDisplay function forces any accumulated updates to
   be displayed.

Resources Convenience Routines

   To obtain the character position of the left-most character on
   the first line displayed in the widget (the value of the
   displayPosition resource), use XawTextTopPosition.

   XawTextPositionfsfunc XawTextTopPosition(Widget w);

   w

   Specifies the Text widget.

   To assign a new selection array to a text widget use
   XawTextSetSelectionArray:

   voidfsfunc XawTextSetSelectionArray(Widget w,
   XawTextSelectType* sarray);

   w

   Specifies the Text widget.

   sarray

   Specifies a selection array as defined in the section called
   \fBText Selections for Application Programmers\fP.

   Calling this function is equivalent to setting the value of the
   selectionTypes resource.

   To move the insertion point to the specified source position,
   use XawTextSetInsertionPoint:

   voidfsfunc XawTextSetInsertionPoint(Widget w, XawTextPosition
   position);

   w

   Specifies the Text widget.

   position

   Specifies the new position for the insertion point.

   See section 5.4 for a description of XawTextPosition. The text
   will be scrolled vertically if necessary to make the line
   containing the insertion point visible. Calling this function
   is equivalent to setting the insertPosition resource.

   To obtain the current position of the insertion point, use
   XawTextGetInsertionPoint:

   XawTextPositionfsfunc XawTextGetInsertionPoint(Widget w);

   w

   Specifies the Text widget.

   See section 5.4 for a description of XawTextPosition. The
   result is equivalent to retrieving the value of the
   insertPosition resource.

   To replace the text source in the specified widget, use
   XawTextSetSource:

   voidfsfunc XawTextSetSource(Widget w, Widget source,
   XawTextPosition position);

   w

   Specifies the Text widget.

   source

   Specifies the text source object.

   position

   Specifies character position that will become the upper left
   hand corner of the displayed text. This is usually set to zero.

   See section 5.4 for a description of XawTextPosition. A display
   update will be performed if redisplay is enabled.

   To obtain the current text source for the specified widget, use
   XawTextGetSource:

   Widgetfsfunc XawTextGetSource(Widget w);

   w

   Specifies the Text widget.

   This function returns the text source that this Text widget is
   currently using.

   To enable and disable the insertion point, use
   XawTextDisplayCaret:

   voidfsfunc XawTextDisplayCaret(Widget w, Boolean visible);

   w

   Specifies the Text widget.

   visible

   Specifies whether or not the caret should be displayed.

   If visible is False the insertion point will be disabled. The
   marker is re-enabled either by setting visible to True, by
   calling XtSetValues, or by executing the display-caret action
   routine.

Customizing the Text Widget

   The remainder of this chapter will describe customizing the
   Text widget. The Text widget may be customized by subclassing,
   or by creating new sources and sinks. Subclassing is described
   in detail in Chapter 7; this section will describe only those
   things that are specific to the Text widget. Attributes of the
   Text widget base class and creating new sources and sinks will
   be discussed.

   The Text widget is made up of a number of different pieces,
   with the Text widget as the base widget class. It and the
   AsciiText widget are the only true "widgets" in the Text widget
   family. The other pieces (sources and sinks) are X Toolkit
   objects and have no window associated with them. No source or
   sink is useful unless assigned to a Text widget.

   Each of the following pieces of the Text widget has a specific
   purpose, and will be, or has been, discussed in detail in this
   chapter:

   Text

   This is the glue that binds everything else together. This
   widget reads the text data from the source, and displays the
   information in the sink. All translations and actions are
   handled in the Text widget itself.

   TextSink

   This object is responsible for displaying and clearing the
   drawing area. It also reports the configuration of the window
   that contains the drawing area. The TextSink does not have its
   own window; instead it does its drawing on the Text widget's
   window.

   TextSrc

   This object is responsible for reading, editing and searching
   through the text buffer.

   AsciiSink

   This object is a subclass of the TextSink and knows how to
   display ASCII text. Support has been added to display any 8-bit
   character set, given the font.

   MultiSink

   This object is a subclass of the TextSink and knows how to
   display font sets.

   AsciiSrc

   This object is a subclass of the TextSrc and knows how to read
   strings and files.

   MultiSrc

   This object is a subclass of the TextSrc and knows how to read
   strings and multibyte files, converting them to wide characters
   based on locale.

   AsciiText

   This widget is a subclass of the Text widget. When created, the
   AsciiText automatically creates and attaches either an AsciiSrc
   and AsciiSink, or a MultiSrc and MultiSink, to itself. The
   AsciiText provides the simplest interface to the Athena Text
   widgets.

Text Widget

Application Header file     <X11/Xaw/Text.h>
Class Header file           <X11/Xaw/TextP.h>
Class                       textWidgetClass
Class Name                  Text
Superclass                  Simple

   The Text widget is the glue that binds all the other pieces
   together, it maintains the internal state of the displayed
   text, and acts as a mediator between the source and sink.

   This section lists the resources that are actually part of the
   Text widget, and explains the functionality provided by each.

Resources

   When creating a Text widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoFill AutoFill Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   bottomMargin Margin Position   2
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   XC_xterm
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   displayCaret Output Boolean   True
   displayPosition TextPosition XawTextPosition   0
   height Height Dimension A Font height + margins
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   insertPosition TextPosition int   0
   leftMargin Margin Position   2
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize XawTextResizeMode   XawtextResizeNever
   rightMargin Margin Position   4
   screen Screen Pointer R Parent's Screen
   scrollHorizontal Scroll ScrollMode   XawtextScrollNever
   scrollVertical Scroll XawTextScrollMode   XawtextScrollNever
   selectTypes SelectTypes XawTextSelectType*   See above
   sensitive Sensitive Boolean   True
   textSink TextSink Widget   NULL
   textSource TextSource Widget   NULL
   topMargin Margin Position   2
   translations Translations TranslationTable   See above
   unrealizeCallback Callback XtCallbackList   NULL
   width Width Dimension   100
   wrap Wrap WrapMode   XawtextWrapNever
   x Position Position   0
   y Position Position   0

TextSink Object



Application Header file <X11/Xaw/TextSink.h>

Class Header file       <X11/Xaw/TextSinkP.h>

Class           textSinkObjectClass

Class Name      TextSink

Superclass      Object

   The TextSink object is the root object for all text sinks. Any
   new text sink objects should be subclasses of the TextSink
   Object. The TextSink Class contains all methods that the Text
   widget expects a text sink to export.

   Since all text sinks will have some resources in common, the
   TextSink defines a few new resources.

Resources

   When creating an TextSink object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

        Name         Class         Type      Notes    Default Value
     background    Background     Pixel            XtDefaultBackground
   destroyCallback  Callback  XtCallbackList              NULL
     foreground    Foreground     Pixel            XtDefaultForeground
          _

Subclassing the TextSink

   The only purpose of the TextSink Object is to be subclassed. It
   contains the minimum set of class methods that all text sinks
   must have. While all may be inherited, the direct descendant of
   TextSink must specify some of them as TextSink does contain
   enough information to be a valid text sink by itself. Do not
   try to use the TextSink as a valid sink for the Text widget; it
   is not intended to be used as a sink by itself.
   Function Inherit with Public Interface must specify
   DisplayText XtInheritDisplayText XawTextSinkDisplayText yes
   InsertCursor XtInheritInsertCursor XawTextSinkInsertCursor yes
   ClearToBackground XtInheritClearToBackground
   XawTextSinkClearToBackground no
   FindPosition XtInheritFindPosition XawTextSinkFindPosition yes
   FindDistance XtInheritFindDistance XawTextSinkFindDistance yes
   Resolve XtInheritResolve XawTextSinkResolve yes
   MaxLines XtInheritMaxLines XawTextSinkMaxLines no
   MaxHeight XtInheritMaxHeight XawTextSinkMaxHeight no
   SetTabs XtInheritSetTabs XawTextSinkSetTabs no
   GetCursorBounds XtInheritGetCursorBounds
   XawTextSinkGetCursorBounds yes

Displaying Text

   To display a section of the text buffer contained in the text
   source use the function DisplayText:

   voidfsfunc DisplayText(Widget w, Positionx, y,
   XawTextPositionpos1, pos2, Boolean highlight);

   w

   Specifies the TextSink object.

   x

   Specifies the x location to start drawing the text.

   y

   Specifies the y location to start drawing text.

   pos1

   Specifies the location within the text source of the first
   character to be printed.

   pos2

   Specifies the location within the text source of the last
   character to be printed.

   highlight

   Specifies whether or not to paint the text region highlighted.

   The Text widget will only pass one line at a time to the text
   sink, so this function does not need to know how to line feed
   the text. It is acceptable for this function to just ignore
   Carriage Returns. x and y denote the upper left hand corner of
   the first character to be displayed.

Displaying the Insert Point

   The function that controls the display of the text cursor is
   InsertCursor. This function will be called whenever the text
   widget desires to change the state of, or move the insert
   point.

   voidfsfunc InsertCursor(Widget w, Positionx, y,
   XawTextInsertState state);

   w

   Specifies the TextSink object.

   x

   Specifies the x location of the cursor in Pixels.

   y

   Specifies the y location of the cursor in Pixels.

   state

   Specifies the state of the cursor, may be one of XawisOn or
   XawisOff.

   X and y denote the upper left hand corner of the insert point.

Clearing Portions of the Text window

   To clear a portion of the Text window to its background color,
   the Text widget will call ClearToBackground. The TextSink
   object already defines this function as calling XClearArea on
   the region passed. This behavior will be used if you specify
   XtInheritClearToBackground for this method.

   voidfsfunc ClearToBackground(Widget w, Positionx, y,
   Dimensionwidth, height);

   w

   Specifies the TextSink object.

   x

   Specifies the x location, in pixels, of the Region to clear.

   y

   Specifies the y location, in pixels, of the Region to clear.

   width

   Specifies the width, in pixels, of the Region to clear.

   height

   Specifies the height, in pixels, of the Region to clear.

   X and y denote the upper left hand corner of region to clear.

Finding a Text Position Given Pixel Values

   To find the text character position that will be rendered at a
   given x location the Text widget uses the function
   FindPosition:

   voidfsfunc FindPosition(Widget w, XawTextPosition fromPos,
   intfromX, width, Boolean stopAtWordBreak, XawTextPosition
   *pos_return, int*width_return, *height_return);

   w

   Specifies the TextSink object.

   fromPos

   Specifies a reference position, usually the first character in
   this line. This character is always to the left of the desired
   character location.

   fromX

   Specifies the distance that the left edge of fromPos is from
   the left edge of the window. This is the reference x location
   for the reference position.

   width

   Specifies the distance, in pixels, from the reference position
   to the desired character position.

   stopAtWordBreak

   Specifies whether or not the position that is returned should
   be forced to be on a word boundary.

   pos_return

   Returns the character position that corresponds to the location
   that has been specified, or the work break immediately to the
   left of the position if stopAtWordBreak is True.

   width_return

   Returns the actual distance between fromPos and pos_return.

   height_return

   Returns the maximum height of the text between fromPos and
   pos_return.

   This function need make no attempt to deal with line feeds. The
   text widget will only call it one line at a time.

   Another means of finding a text position is provided by the
   Resolve function:

   voidfsfunc Resolve(Widget w, XawTextPosition fromPos, intfromX,
   width, XawTextPosition *pos_return);

   w

   Specifies the TextSink object.

   fromPos

   Specifies a reference position, usually the first character in
   this line. This character is always to the left of the desired
   character location.

   fromX

   Specifies the distance that the left edge of fromPos is from
   the left edge of the window. This is the reference x location
   for the reference position.

   width

   Specifies the distance, in pixels, from the reference position
   to the desired character position.

   pos_return

   Returns the character position that corresponds to the location
   that has been specified, or the word break immediately to the
   left if stopAtWordBreak is True.

   This function need make no attempt to deal with line feeds. The
   text widget will only call it one line at a time. This is a
   more convenient interface to the FindPosition function, and
   provides a subset of its functionality.

Finding the Distance Between two Text Positions

   To find the distance in pixels between two text positions on
   the same line use the function FindDistance.

   voidfsfunc FindDistance(Widget w, XawTextPositionfromPos,
   toPos, int fromX, XawTextPosition *pos_return,
   int*width_return, *height_return);

   w

   Specifies the TextSink object.

   fromPos

   Specifies the text buffer position, in characters, of the first
   position.

   fromX

   Specifies the distance that the left edge of fromPos is from
   the left edge of the window. This is the reference x location
   for the reference position.

   toPos

   Specifies the text buffer position, in characters, of the
   second position.

   resWidth

   Return the actual distance between fromPos and pos_return.

   resPos

   Returns the character position that corresponds to the actual
   character position used for toPos in the calculations. This may
   be different than toPos, for example if fromPos and toPos are
   on different lines in the file.

   height_return

   Returns the maximum height of the text between fromPos and
   pos_return.

   This function need make no attempt to deal with line feeds. The
   Text widget will only call it one line at a time.

Finding the Size of the Drawing area

   To find the maximum number of lines that will fit into the
   current Text widget, use the function MaxLines. The TextSink
   already defines this function to compute the maximum number of
   lines by using the height of font.

   intfsfunc MaxLines(Widget w, Dimension height);

   w

   Specifies the TextSink object.

   height

   Specifies the height of the current drawing area.

   Returns the maximum number of lines that will fit in height.

   To find the height required for a given number of text lines,
   use the function MaxHeight. The TextSink already defines this
   function to compute the maximum height of the window by using
   the height of font.

   intfsfunc MaxHeight(Widget w, int lines);

   w

   Specifies the TextSink object.

   height

   Specifies the height of the current drawing area.

   Returns the height that will be taken up by the number of lines
   passed.

Setting the Tab Stops

   To set the tab stops for a text sink use the SetTabs function.
   The TextSink already defines this function to set the tab x
   location in pixels to be the number of characters times the
   figure width of font.

   voidfsfunc SetTabs(Widget w, inttab_count, *tabs);

   w

   Specifies the TextSink object.

   tab_count

   Specifies the number of tabs passed in tabs.

   tabs

   Specifies the position, in characters, of the tab stops.

   This function is responsible for the converting character
   positions passed to it into whatever internal positions the
   TextSink uses for tab placement.

Getting the Insert Point's Size and Location

   To get the size and location of the insert point use the
   GetCursorBounds function.

   voidfsfunc GetCursorBounds(Widget w, XRectangle *rect_return);

   w

   Specifies the TextSinkObject.

   rect_return

   Returns the location and size of the insert point.

   Rect will be filled with the current size and location of the
   insert point.

TextSrc Object

Application Header file <X11/Xaw/TextSrc.h>
Class Header file       <X11/Xaw/TextSrcP.h>
Class                   textSrcObjectClass
Class Name              TextSrc
Superclass              Object

   The TextSrc object is the root object for all text sources. Any
   new text source objects should be subclasses of the TextSrc
   Object. The TextSrc Class contains all methods the Text widget
   expects a text source to export.

   Since all text sources will have some resources in common the
   TextSrc defines a few new resources.

Resources

   When creating an TextSrc object instance, the following
   resources are retrieved from the argument list or from the
   resource database:
        Name        Class        Type      Notes Default Value
   destroyCallback Callback XtCallbackList           NULL
      editType     EditType    EditMode              NULL

Subclassing the TextSrc

   The only purpose of the TextSrc Object is to be subclassed. It
   contains the minimum set of class methods that all text sources
   must have. All class methods of the TextSrc must be defined, as
   the Text widget uses them all. While all may be inherited, the
   direct descendant of TextSrc must specify some of them as
   TextSrc does not contain enough information to be a valid text
   source by itself. Do not try to use the TextSrc as a valid
   source for the Text widget; it is not intended to be used as a
   source by itself and bad things will probably happen.
   Function Inherit with Public Interface must specify
   Read XtInheritRead XawTextSourceRead yes
   Replace XtInheritReplace XawTextSourceReplace no
   Scan XtInheritScan XawTextSourceScan yes
   Search XtInheritSearch XawTextSourceSearch no
   SetSelection XtInheritSetSelection XawTextSourceSetSelection no
   ConvertSelection XtInheritConvertSelection
   XawTextSourceConvertSelection no

Reading Text.

   To read the text in a text source use the Read function:

   XawTextPositionfsfunc Read(Widget w, XawTextPosition pos,
   XawTextBlock *text_return, int length);

   w

   Specifies the TextSrc object.

   pos

   Specifies the position of the first character to be read from
   the text buffer.

   text

   Returns the text read from the source.

   length

   Specifies the maximum number of characters the TextSrc should
   return to the application in text_return.

   This function returns the text position immediately after the
   characters read from the text buffer. The function is not
   required to read length characters if that many characters are
   in the file, it may break at any point that is convenient to
   the internal structure of the source. It may take several calls
   to Read before the desired portion of the text buffer is fully
   retrieved.

Replacing Text.

   To replace or edit the text in a text buffer use the Replace
   function:

   XawTextPositionfsfunc Replace(Widget w, XawTextPositionstart,
   end, XawTextBlock *text);

   w

   Specifies the TextSrc object.

   start

   Specifies the position of the first character to be removed
   from the text buffer. This is also the location to begin
   inserting the new text.

   end

   Specifies the position immediately after the last character to
   be removed from the text buffer.

   text

   Specifies the text to be added to the text source.

   This function can return any of the following values:

   XawEditDone

   The text replacement was successful.

   XawPositionError

   The edit mode is XawtextAppend and start is not the last
   character of the source.

   XawEditError

   Either the Source was read-only or the range to be deleted is
   larger than the length of the Source.

   The Replace arguments start and end represent the text source
   character positions for the existing text that is to be
   replaced by the text in the text block. The characters from
   start up to but not including end are deleted, and the buffer
   specified by the text block is inserted in their place. If
   start and end are equal, no text is deleted and the new text is
   inserted after start.

Scanning the TextSrc

   To search the text source for one of the predefined boundary
   types use the Scan function:

   XawTextPositionfsfunc Scan(Widget w, XawTextPosition position,
   XawTextScanType type, XawTextScanDirection dir, int count,
   Boolean include);

   w

   Specifies the TextSrc object.

   position

   Specifies the position to begin scanning the source.

   type

   Specifies the type of boundary to scan for, may be one of:
   XawstPosition, XawstWhiteSpace, XawstEOL, XawstParagraph,
   XawstAll. The exact meaning of these boundaries is left up to
   the individual text source.

   dir

   Specifies the direction to scan, may be either XawsdLeft to
   search backward, or XawsdRight to search forward.

   count

   Specifies the number of boundaries to scan for.

   include

   Specifies whether the boundary itself should be included in the
   scan.

   The Scan function returns the position in the text source of
   the desired boundary. It is expected to return a valid address
   for all calls made to it, thus if a particular request is made
   that would take the text widget beyond the end of the source it
   must return the position of that end.

Searching through a TextSrc

   To search for a particular string use the Search function.

   XawTextPositionfsfunc Search(Widget w, XawTextPosition
   position, XawTextScanDirection dir, XawTextBlock *text);

   w

   Specifies the TextSrc object.

   position

   Specifies the position to begin the search.

   dir

   Specifies the direction to search, may be either XawsdLeft to
   search backward, or XawsdRight to search forward.

   text

   Specifies a text block containing the text to search for.

   This function will search through the text buffer attempting to
   find a match for the string in the text block. If a match is
   found in the direction specified, then the character location
   of the first character in the string is returned. If no text
   was found then XawTextSearchError is returned.

Text Selections

   While many selection types are handled by the Text widget, text
   sources may have selection types unknown to the Text widget.
   When a selection conversion is requested by the X server the
   Text widget will first call the ConvertSelection function, to
   attempt the selection conversion.

   Booleanfsfunc ConvertSelections(Widget w,
   Atom*selection,*target, *type, caddr_t *value_return,
   unsignedlong *length_return, int *format_return);

   w

   Specifies the TextSrc object.

   selection

   Specifies the type of selection that was requested (e.g.
   PRIMARY).

   target

   Specifies the type of the selection that has been requested,
   which indicates the desired information about the selection
   (e.g. Filename, Text, Window).

   type

   Specifies a pointer to the atom into which the property type of
   the converted value of the selection is to be stored. For
   instance, either file name or text might have property type
   XA_STRING.

   value_return

   Returns a pointer into which a pointer to the converted value
   of the selection is to be stored. The selection owner is
   responsible for allocating this storage. The memory is
   considered owned by the toolkit, and is freed by XtFree when
   the Intrinsics selection mechanism is done with it.

   length_return

   Returns a pointer into which the number of elements in value is
   to be stored. The size of each element is determined by format.

   format_return

   Returns a pointer into which the size in bits of the data
   elements of the selection value is to be stored.

   If this function returns True then the Text widget will assume
   that the source has taken care of converting the selection,
   Otherwise the Text widget will attempt to convert the selection
   itself.

   If the source needs to know when the text selection is modified
   it should define a SetSelection procedure:

   voidfsfunc SetSelection(Widget w, XawTextPositionstart, end,
   Atom selection);

   w

   Specifies the TextSrc object.

   start

   Specifies the character position of the beginning of the new
   text selection.

   end

   Specifies the character position of the end of the new text
   selection.

   selection

   Specifies the type of selection that was requested (e.g.
   PRIMARY).

Ascii Sink Object and Multi Sink Object



Application Header file <X11/Xaw/AsciiSink.h>

Class Header file       <X11/Xaw/AsciiSinkP.h>

Class           asciiSinkObjectClass

Class Name      AsciiSink

Superclass      TextSink

   The AsciiSink or MultiSink object is used by a text widget to
   render the text. Depending on its international resource, a
   AsciiText widget will create one or the other of these when the
   AsciiText itself is created. Both types are nearly identical;
   the following discussion applies to both, with MultiSink
   differences noted only as they occur. The AsciiSink will
   display all printing characters in an 8 bit font, along with
   handling Tab and Carriage Return. The name has been left as
   ``AsciiSink'' for compatibility. \fIThe MultiSink will display
   all printing characters in a font set, along with handling Tab
   and Carriage Return.\fP The source object also reports the text
   window metrics to the text widgets.

Resources

   When creating an AsciiSink object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

         Name          Class         Type      Notes    Default Value
      background     Background     Pixel            XtDefaultBackground
   destroyCallback    Callback  XtCallbackList              NULL
  displayNonprinting   Output      Boolean                  True
         echo          Output      Boolean                  True
         font           Font     XFontStruct*           XtDefaultFont
       fontSet        FontSet      XFontSet           XtDefaultFontSet
      foreground     Foreground     Pixel            XtDefaultForeground
          _

   This resource is retrieved by the AsciiSink instead of being
   copied from the Text widget.

   The text font to use when displaying the string. (This resource
   is present in the AsciiSink, but not the MultiSink.)

   The text font set to use when displaying the string. (This
   resource is present in the MultiSink, but not the AsciiSink.)

Ascii Source Object and Multi Source Object



Application Header file <X11/Xaw/AsciiSrc.h> or <X11/Xaw/MultiSrc.h>

Class Header file       <X11/Xaw/AsciiSrcP.h> or  <X11/Xaw/MultiSrcP.h>

Class           asciiSrcObjectClass or multiSrcObjectClass

Class Name      AsciiSrc or MultiSrc

Superclass      TextSource

   The AsciiSrc or MultiSrc object is used by a text widget to
   read the text from a file or string in memory. Depending on its
   international resource, an AsciiText widget will create one or
   the other of these when the AsciiText itself is created. Both
   types are nearly identical; the following discussion applies to
   both, with MultiSrc differences noted only as they occur.

   The AsciiSrc understands all Latin1 characters plus Tab and
   Carriage Return. \fIThe MultiSrc understands any set of
   character sets that the underlying X implementation's
   internationalization handles.\fP

   The AsciiSrc can be either of two types: XawAsciiFile or
   XawAsciiString.

   AsciiSrc objects of type XawAsciiFile read the text from a file
   and store it into an internal buffer. This buffer may then be
   modified, provided the text widget is in the correct edit mode,
   just as if it were a source of type XawAsciiString. Unlike R3
   and earlier versions of the AsciiSrc, it is now possible to
   specify an editable disk source. The file is not updated,
   however, until a call to XawAsciiSave is made. When the source
   is in this mode the useStringInPlace resource is ignored.

   AsciiSrc objects of type XawAsciiString have the text buffer
   implemented as a string. \fIMultiSrc objects of type
   XawAsciiString have the text buffer implemented as a wide
   character string.\fP The string owner is responsible for
   allocating and managing storage for the string.

   In the default case for AsciiSrc objects of type
   XawAsciiString, the resource useStringInPlace is false, and the
   widget owns the string. The initial value of the string
   resource, and any update made by the application programmer to
   the string resource with XtSetValues, is copied into memory
   private to the widget, and managed internally by the widget.
   The application writer does not need to worry about running out
   of buffer space (subject to the total memory available to the
   application). The performance does not decay linearly as the
   buffer grows large, as is necessarily the case when the text
   buffer is used in place. The application writer must use
   XtGetValues to determine the contents of the text buffer, which
   will return a copy of the widget's text buffer as it existed at
   the time of the XtGetValues call. This copy is not affected by
   subsequent updates to the text buffer, i.e., it is not updated
   as the user types input into the text buffer. This copy is
   freed upon the next call to XtGetValues to retrieve the string
   resource; however, to conserve memory, there is a convenience
   routine, XawAsciiSourceFreeString, allowing the application
   programmer to direct the widget to free the copy.

   When the resource useStringInPlace is true and the AsciiSrc
   object is of type XawAsciiString, the application is the string
   owner. The widget will take the value of the string resource as
   its own text buffer, and the length resource indicates the
   buffer size. In this case the buffer contents change as the
   user types at the widget; it is not necessary to call
   XtGetValues on the string resource to determine the contents of
   the buffer-it will simply return the address of the
   application's implementation of the text buffer.

Resources

   When creating an AsciiSrc object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

       Name            Class            Type      Notes  Default Value
     callback         Callback     XtCallbackList             NULL
 dataCompression  DataCompression     Boolean                 True
 destroyCallback      Callback        Callback                NULL
     editType         EditType        EditMode            XawtextRead
      length           Length           Int         A   length of string
    pieceSize        PieceSize          Int                  BUFSIZ
      string           String          String                 NULL
       type             Type         AsciiType           XawAsciiString
 useStringInPlace UseStringInPlace    Boolean                False
        _

Convenience Routines

   The AsciiSrc has a few convenience routines that allow the
   application programmer quicker or easier access to some of the
   commonly used functionality of the AsciiSrc.

Conserving Memory

   When the AsciiSrc widget is not in useStringInPlace mode space
   must be allocated whenever the file is saved, or the string is
   requested with a call to XtGetValues. This memory is allocated
   on the fly, and remains valid until the next time a string
   needs to be allocated. You may save memory by freeing this
   string as soon as you are done with it by calling
   XawAsciiSourceFreeString.

   voidfsfunc XawAsciiSourceFreeString(Widget w);

   w

   Specifies the AsciiSrc object.

   This function will free the memory that contains the string
   pointer returned by XtGetValues. This will normally happen
   automatically when the next call to XtGetValues occurs, or when
   the widget is destroyed.

Saving Files

   To save the changes made in the current text source into a file
   use XawAsciiSave.

   Booleanfsfunc XawAsciiSave(Widget w);

   w

   Specifies the AsciiSrc object.

   XawAsciiSave returns True if the save was successful. It will
   update the file named in the string resource. If the buffer has
   not been changed, no action will be taken. This function only
   works on an AsciiSrc of type XawAsciiFile.

   To save the contents of the current text buffer into a named
   file use XawAsciiSaveAsFile.

   Booleanfsfunc XawAsciiSaveAsFile(Widget w, String name);

   w

   Specifies the AsciiSrc object.

   name

   The name of the file to save the current buffer into.

   This function returns True if the save was successful.
   XawAsciiSaveAsFile will work with a buffer of either type
   XawAsciiString or type XawAsciiFile.

Seeing if the Source has Changed

   To find out if the text buffer in an AsciiSrc object has
   changed since the last time it was saved with XawAsciiSave or
   queried use XawAsciiSourceChanged.

   Booleanfsfunc XawAsciiSourceChanged(Widget w);

   w

   Specifies the AsciiSrc object.

   This function will return True if the source has changed since
   the last time it was saved or queried. The internal change flag
   is reset whenever the string is queried via XtGetValues or the
   buffer is saved via XawAsciiSave.

Ascii Text Widget



Application Header file <X11/Xaw/AsciiText.h>

ClassHeader file        <X11/Xaw/AsciiTextP.h>

Class           asciiTextWidgetClass

Class Name      Text

Superclass      Text
Sink Name       textSink
Source Name     textSource

   For the ease of internationalization, the AsciiText widget
   class name has not been changed, although it is actually able
   to support non-ASCII locales. The AsciiText widget is really a
   collection of smaller parts. It includes the Text widget
   itself, a ``Source'' (which supports memory management), and a
   ``Sink'' (which handles the display). There are currently two
   supported sources, the AsciiSrc and MultiSrc, and two supported
   sinks, the AsciiSink and MultiSink. Some of the resources
   listed below are not actually resources of the AsciiText, but
   belong to the associated source or sink. This is is noted in
   the explanation of each resource where it applies. When
   specifying these resources in a resource file it is necessary
   to use *AsciiText*resource_name instead of
   *AsciiText.resource_name, since they actually belong to the
   children of the AsciiText widget, and not the AsciiText widget
   itself. However, these resources may be set directly on the
   AsciiText widget at widget creation time, or via XtSetValues.

Resources

   When creating an AsciiText widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoFill AutoFill Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   bottomMargin Margin Position   2
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   XC_xterm
   cursorName Cursor String   NULL
   dataCompression DataCompression Boolean   True
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   displayCaret Output Boolean   True
   displayNonprinting Output Boolean   True
   displayPosition TextPosition XawTextPosition   0
   echo Output Boolean   True
   editType EditType XawTextEditType   XawtextRead
   font Font XFontStruct*   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Font height + margins
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   insertPosition TextPosition int   0
   international International Boolean C False
   leftMargin Margin Dimension   2
   length Length int A length of string
   mappedWhenManaged MappedWhenManaged Boolean   True
   pieceSize PieceSize XawTextPosition   BUFSIZ
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize XawTextResizeMode   XawtextResizeNever
   rightMargin Margin Position   2
   screen Screen Screen R Parent's Screen
   scrollHorizontal Scroll XawTextScrollMode   XawtextScrollNever
   scrollVertical Scroll XawTextScrollMode   XawtextScrollNever
   selectTypes SelectTypes XawTextSelectType*   See above
   sensitive Sensitive Boolean   True
   string String String   NULL
   textSink TextSink Widget   An AsciiSink
   textSource TextSource Widget   An AsciiSrc
   topMargin Margin Position   2
   translations Translations TranslationTable   See above
   type Type XawAsciiType   XawAsciiString
   useStringInPlace UseStringInPlace Boolean   False
   width Width Dimension   100
   wrap Wrap WrapMode   XawtextWrapNever
   x Position Position   0
   y Position Position   0

Chapter 6. Composite and Constraint Widgets

   Table of Contents

   Box Widget

        Resources
        Layout Semantics

   Dialog Widget

        Resources
        Constraint Resources
        Layout Semantics
        Automatically Created Children.
        Convenience Routines

   Form Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

   Paned Widget

        Using the Paned Widget
        Resources
        Constraint Resources
        Layout Semantics
        Grip Translations
        Convenience Routines

   Porthole Widget

        Resources
        Layout Semantics
        Porthole Callbacks

   Tree Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

   Viewport Widget

        Resources
        Layout Semantics

   These widgets may contain arbitrary widget children. They
   implement a policy for the size and location of their children.

   Box

   This widget will pack its children as tightly as possible in
   non-overlapping rows.

   Dialog

   An implementation of a commonly used interaction semantic to
   prompt for auxiliary input from the user, such as a filename.

   Form

   A more sophisticated layout widget that allows the children to
   specify their positions relative to the other children, or to
   the edges of the Form.

   Paned

   Allows children to be tiled vertically or horizontally.
   Controls are also provided to allow the user to dynamically
   resize the individual panes.

   Porthole

   Allows viewing of a managed child which is as large as, or
   larger than its parent, typically under control of a Panner
   widget.

   Tree

   Provides geometry management of widgets arranged in a directed,
   acyclic graph.

   Viewport

   Consists of a frame, one or two scrollbars, and an inner
   window. The inner window can contain all the data that is to be
   displayed. This inner window will be clipped by the frame with
   the scrollbars controlling which section of the inner window is
   currently visible.

Note

   The geometry management semantics provided by the X Toolkit
   give full control of the size and position of a widget to the
   parent of that widget. While the children are allowed to
   request a certain size or location, it is the parent who makes
   the final decision. Many of the composite widgets here will
   deny any geometry request from their children by default. If a
   child widget is not getting the expected size or location, it
   is most likely the parent disallowing a request, or
   implementing semantics slightly different than those expected
   by the application programmer.

   If the application wishes to change the size or location of any
   widget it should make a call to XtSetValues. This will allow
   the widget to ask its parent for the new size or location. As
   noted above the parent is allowed to refuse this request, and
   the child must live with the result. If the application is
   unable to achieve the desired semantics, then perhaps it should
   use a different composite widget. Under no circumstances should
   an application programmer resort to XtMoveWidget or
   XtResizeWidget; these functions are exclusively for the use of
   Composite widget implementors.

   For more information on geometry management consult the X
   Toolkit Intrinsics - C Language Interface.

Box Widget




Application Header file <X11/Xaw/Box.h>

Class Header file       <X11/Xaw/BoxP.h>

Class           boxWidgetClass

Class Name      Box

Superclass      Composite


   The Box widget provides geometry management of arbitrary
   widgets in a box of a specified dimension. The children are
   rearranged when resizing events occur either on the Box or its
   children, or when children are managed or unmanaged. The Box
   widget always attempts to pack its children as tightly as
   possible within the geometry allowed by its parent.

   Box widgets are commonly used to manage a related set of
   buttons and are often called ButtonBox widgets, but the
   children are not limited to buttons. The Box's children are
   arranged on a background that has its own specified dimensions
   and color.

Resources

   When creating a Box widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A see Layout Semantics
   hSpace HSpace Dimension   4
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   orientation Orientation Orientation   XtorientVertical
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   vSpace VSpace Dimension   4
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0
   _

   hSpace

   vSpace

   The amount of space, in pixels, to leave between the children.
   This resource specifies the amount of space left between the
   outermost children and the edge of the box.

   orientation

   Specifies whether the preferred shape of the box (i.e. the
   result returned by the query_geometry class method) is tall and
   narrow XtorientVertical or short and wide XtorientHorizontal.
   When the Box is a child of a parent which enforces width
   constraints, it is usually better to specify XtorientVertical
   (the default). When the parent enforces height constraints, it
   is usually better to specify XtorientHorizontal.

Layout Semantics

   Each time a child is managed or unmanaged, the Box widget will
   attempt to reposition the remaining children to compact the
   box. Children are positioned in order left to right, top to
   bottom. The packing algorithm used depends on the orientation
   of the Box.

   XtorientVertical

   When the next child does not fit on the current row, a new row
   is started. If a child is wider than the width of the box, the
   box will request a larger width from its parent and will begin
   the layout process from the beginning if a new width is
   granted.

   XtorientHorizontal

   When the next child does not fit on the current row, the Box
   widens if possible (so as to keep children on a single row);
   otherwise a new row is started.

   After positioning all children, the Box widget attempts to
   shrink its own size to the minimum dimensions required for the
   layout.

Dialog Widget




Application Header file <X11/Xaw/Dialog.h>

Class Header file       <X11/Xaw/DialogP.h>

Class           dialogWidgetClass

Class Name      Dialog

Superclass      Form


   The Dialog widget implements a commonly used interaction
   semantic to prompt for auxiliary input from a user. For
   example, you can use a Dialog widget when an application
   requires a small piece of information, such as a filename, from
   the user. A Dialog widget, which is simply a special case of
   the Form widget, provides a convenient way to create a
   preconfigured form.

   The typical Dialog widget contains three areas. The first line
   contains a description of the function of the Dialog widget,
   for example, the string Filename:. The second line contains an
   area into which the user types input. The third line can
   contain buttons that let the user confirm or cancel the Dialog
   input. Any of these areas may be omitted by the application.

Resources

   When creating a Dialog widget instance, the following resources
   are retrieved from the argument list or the resource database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   defaultDistance Thickness int   4
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A Enough space to contain all children
   icon Icon Bitmap   None
   label Label String   "label"
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   value Value String   no value widget
   width Width Dimension A Enough space to contain all children
   x Position Position   0
   y Position Position   0
   _

   icon

   A pixmap image to be displayed immediately to the left of the
   Dialog widget's label.

   label

   A string to be displayed at the top of the Dialog widget.

   value

   An initial value for the string field that the user will enter
   text into. By default, no text entry field is available to the
   user. Specifying an initial value for value activates the text
   entry field. If string input is desired, but no initial value
   is to be specified then set this resource to "" (empty string).

Constraint Resources

   Each child of the Dialog widget may request special layout
   resources be applied to it. These constraint resources allow
   the Dialog widget's children to specify individual layout
   requirements.

       Name        Class      Type     Notes       Default Value
      bottom       Edge    XawEdgeType               XawRubber
     fromHoriz    Widget     Widget          NULL (left edge of Dialog)
     fromVert     Widget     Widget          NULL (top edge of Dialog)
   horizDistance Thickness     int            defaultDistance resource
       left        Edge    XawEdgeType               XawRubber
     resizable    Boolean    Boolean                   FALSE
       right       Edge    XawEdgeType               XawRubber
        top        Edge    XawEdgeType               XawRubber
   vertDistance  Thickness     int            defaultDistance resource

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

   The Dialog widget uses two different sets of layout seman-
   tics. One is used when initially laying out the children. The
   other is used when the Dialog is resized.

   The first layout method uses the fromVert mand fromHoriz
   resources to place the children of the Dialog. A single pass is
   made through the Dialog widget's children in the order that
   they were created. Each child is then placed in the Dialog
   widget below or to the right of the widget speci- fied by the
   fromVert mand fromHoriz mresources. The distance the new child
   is placed from its left or upper neighbor is determined by the
   horizDistance mand vertDistance mresources. This implies some
   things about how the order of creation affects the possible
   placement of the children. The Form widget registers a string
   to widget converter which does not postpone conversion and does
   not cache conversion results.

   The second layout method is used when the Dialog is resized. It
   does not matter what causes this resize, and it is possi- ble
   for a resize to happen before the widget becomes visible (due
   to constraints imposed by the parent of the Dialog). This
   layout method uses the bottom , top , left , and right
   resources. These resources are used to determine what will
   happen to each edge of the child when the Dialog is resized. If
   a value of XawChain <something> is specified, the the edge of
   the child will remain a fixed distance from the chain edge of
   the Dialog. For example if XawChainLeft mis specified for the
   right mresource of a child then the right edge of that child
   will remain a fixed distance from the left edge of the Dialog
   widget. If a value of XawRubber mis spec- ified, that edge will
   grow by the same percentage that the Dialog grew. For instance
   if the Dialog grows by 50% the left edge of the child (if
   specified as XawRubber mwill be 50% farther from the left edge
   of the Dialog). One must be very careful when specifying these
   resources, for when they are specified incorrectly children may
   overlap or completely occlude other children when the Dialog
   widget is resized.

   Edge Type Resource Name Description
   XawChainBottom ChainBottom Edge remains a fixed distance from
   bottom of Dialog
   XawChainLeft ChainLeft Edge remains a fixed distance from left
   of Dialog
   XawChainRight ChainRight Edge remains a fixed distance from
   right of Dialog
   XawChainTop ChainTop Edge remains a fixed distance from top of
   Dialog
   XawRubber Rubber Edges will move a proportional distance

Example

   If you wish to force the Dialog to never resize one or more of
   its children then set left and right to XawChainLeft and top
   and bottom to XawChainTop. This will cause the child to remain
   a fixed distance from the top and left edges of the Dialog, and
   to never resize.

Special Considerations

   The Dialog widget automatically sets the top and bottom
   resources for all Children that are subclasses of the Command
   widget, as well as the widget children that are used to contain
   the label, value, and icon. This policy allows the buttons at
   the bottom of the Dialog to interact correctly with the
   predefined children, and makes it possible for a client to
   simply create and manage a new Command button without having to
   specify its constraints.

   The Dialog will also set fromLeft to the last button in the
   Dialog for each new button added to the Dialog widget.

   The automatically added constraints cannot be overridden, as
   they are policy decisions of the Dialog widget. If a more
   flexible Dialog is desired, the application is free to use the
   Form widget to create its own Dialog policy.

Automatically Created Children.

   The Dialog uses Label widgets to contain the label and icon.
   These widgets are named label and icon respectively. The Dialog
   value is contained in an AsciiText widget whose name is value.
   Using XtNameToWidget the application can change those resources
   associated with each of these widgets that are not available
   through the Dialog widget itself.

Convenience Routines

   To return the character string in the text field, use

   Stringfsfunc XawDialogGetValueString(Widget w);

   w

   Specifies the Dialog widget.

   This function returns a copy of the value string of the Dialog
   widget. This string is allocated by the AsciiText widget and
   will remain valid and unchanged until another call to
   XawDialogGetValueString or an XtGetValues call on the value
   widget, when the string will be automatically freed, and a new
   string is returned. This string may be freed earlier by calling
   the function XawAsciiSourceFreeString.

   To add a new button to the Dialog widget use
   XawDialogAddButton.

   voidfsfunc XawDialogAddButton(Widget w, String name,
   XtCallbackProc func, XtPointer client_data);

   w

   Specifies the Dialog widget.

   name

   Specifies the name of the new Command button to be added to the
   Dialog.

   func

   Specifies a callback function to be called when this button is
   activated. If NULL is specified then no callback is added.

   client_data

   Specifies the client_data to be passed to the func.

   This function is merely a shorthand for the code sequence:



{
        Widget button = XtCreateManagedWidget(name, commandWidgetClass,
w, NULL, ZERO);
        XtAddCallback(button, XtNcallback, func, client_data);
}


Form Widget




Application Header file <X11/Xaw/Form.h>

Class Header file       <X11/Xaw/FormP.h>

Class           formWidgetClass

Class Name      Form

Superclass      Constraint


   The Form widget can contain an arbitrary number of children or
   subwidgets. The Form provides geometry management for its
   children, which allows individual control of the position of
   each child. Any combination of children can be added to a Form.
   The initial positions of the children may be computed relative
   to the positions of previously created children. When the Form
   is resized, it computes new positions and sizes for its
   children. This computation is based upon information provided
   when a child is added to the Form.

   The default width of the Form is the minimum width needed to
   enclose the children after computing their initial layout, with
   a margin of defaultDistance at the right and bottom edges. If a
   width and height is assigned to the Form that is too small for
   the layout, the children will be clipped by the right and
   bottom edges of the Form.

Resources

   When creating a Form widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   defaultDistance Thickness int   4
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A Enough space to contain all children
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension A Enough space to contain all children
   x Position Position   0
   y Position Position   0
   _

Constraint Resources

   Each child of the Form widget may request special layout
   resources be applied to it. These constraint resources allow
   the Form widget's children to specify individual layout
   requirements.

       Name        Class      Type     Notes      Default Value
      bottom       Edge    XawEdgeType              XawRubber
     fromHoriz    Widget     Widget          NULL (left edge of Form)
     fromVert     Widget     Widget          NULL (top edge of Form)
   horizDistance Thickness     int           defaultDistance resource
       left        Edge    XawEdgeType              XawRubber
     resizable    Boolean    Boolean                  FALSE
       right       Edge    XawEdgeType              XawRubber
        top        Edge    XawEdgeType              XawRubber
   vertDistance  Thickness     int           defaultDistance resource

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

   The Form widget uses two different sets of layout semantics.
   One is used when initially laying out the children. The other
   is used when the Form is resized.

   The first layout method uses the fromVert and fromHoriz
   resources to place the children of the Form. A single pass is
   made through the Form widget's children in the order that they
   were created. Each child is then placed in the Form widget
   below or to the right of the widget specified by the fromVert
   and fromHoriz resources. The distance the new child is placed
   from its left or upper neighbor is deter- mined by the
   horizDistance and vertDistance resources. This implies some
   things about how the order of creation affects the possible
   placement of the children. The Form widget registers a string
   to widget converter which does not post- pone conversion and
   does not cache conversion results.

   The second layout method is used when the Form is resized. It
   does not matter what causes this resize, and it is possi- ble
   for a resize to happen before the widget becomes visible (due
   to constraints imposed by the parent of the Form). This layout
   method uses the bottom, top, left, and right resources. These
   resources are used to determine what will happen to each edge
   of the child when the Form is resized. If a value of XawChain
   <something> is specified, the the edge of the child will remain
   a fixed distance from the chain edge of the Form. For example
   if XawChainLeft is specified for the right resource of a child
   then the right edge of that child will remain a fixed distance
   from the left edge of the Form widget. If a value of XawRubber
   is specified, that edge will grow by the same percentage that
   the Form grew. For instance if the Form grows by 50% the left
   edge of the child (if specified as XawRubber will be 50%
   farther from the left edge of the Form). One must be very
   careful when specifying these resources, for when they are
   specified incorrectly children may overlap or completely
   occlude other children when the Form widget is resized.

   Edge Type Resource Name Description
   XawChainBottom ChainBottom Edge remains a fixed distance from
   bottom of Form
   XawChainLeft ChainLeft Edge remains a fixed distance from left
   of Form
   XawChainRight ChainRight Edge remains a fixed distance from
   right of Form
   XawChainTop ChainTop Edge remains a fixed distance from top of
   Form
   XawRubber Rubber Edges will move a proportional distance

Example

   If you wish to force the Form to never resize one or more of
   its children, then set left and right to XawChainLeft and top
   and bottom to XawChainTop. This will cause the child to remain
   a fixed distance from the top and left edges of the Form, and
   never to resize.

Convenience Routines

   To force or defer a re-layout of the Form, use

   voidfsfunc XawFormDoLayout(Widget w, Boolean do_layout);

   w

   Specifies the Form widget.

   do_layout

   Specifies whether the layout of the Form widget is enabled
   (True) or disabled (False).

   When making several changes to the children of a Form widget
   after the Form has been realized, it is a good idea to disable
   relayout until after all changes have been made.

Paned Widget




Application Header file <X11/Xaw/Paned.h>

Class Header file       <X11/Xaw/PanedP.h>

Class           panedWidgetClass

Class Name      Paned

Superclass      Constraint


   The Paned widget manages children in a vertically or
   horizontally tiled fashion. The panes may be dynamically
   resized by the user by using the grips that appear near the
   right or bottom edge of the border between two panes.

   The Paned widget may accept any widget class as a pane except
   Grip. Grip widgets have a special meaning for the Paned widget,
   and adding a Grip as its own pane will confuse the Paned
   widget.

Using the Paned Widget

   The grips allow the panes to be resized by the user. The
   semantics of how these panes resize is somewhat complicated,
   and warrants further explanation here. When the mouse pointer
   is positioned on a grip and pressed, an arrow is displayed that
   indicates the pane that is to be to be resized. While keeping
   the mouse button down, the user can move the grip up and down
   (or left and right). This, in turn, changes the size of the
   pane. The size of the Paned widget will not change. Instead, it
   chooses another pane (or panes) to resize. For more details on
   which pane it chooses to resize, see Layout Semantics.

   One pointer binding allows the border between two panes to be
   moved, without affecting any of the other panes. When this
   occurs the pointer will change to an arrow that points along
   the pane border.

   The default bindings for the Paned widget's grips are:
   Mouse button Pane to Resize - Vertical Pane to Resize -
   Horizontal
   1 (left) above the grip left of the grip
   2 (middle) adjust border adjust border
   3 (right) below the grip right of the grip
   _

Resources

   When creating a Paned widget instance, the following resources
   are retrieved from the argument list or the resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   betweenCursor Cursor Cursor A Depends on orientation
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   gripCursor Cursor Cursor A Depends on orientation
   gripIndent GripIndent Position   10
   gripTranslations Translations TranslationTable   see below
   height Height Dimension A Depends on orientation
   horizontalBetweenCursor Cursor Cursor   sb_up_arrow
   horizontalGripCursor Cursor Cursor   sb_h_double_arrow
   internalBorderColor BorderColor Pixel   XtDefaultForeground
   internalBorderWidth BorderWidth Dimension   1
   leftCursor Cursor Cursor   sb_left_arrow
   lowerCursor Cursor Cursor   sb_down_arrow
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   orientation Orientation Orientation   XtorientVertical
   refigureMode Boolean Boolean   True
   rightCursor Cursor Cursor   sb_right_arrow
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   upperCursor Cursor Cursor   sb_up_arrow
   verticalBetweenCursor Cursor Cursor   sb_left_arrow
   verticalGripCursor Cursor Cursor   sb_v_double_arrow
   width Width Dimension A Depends on orientation
   x Paned Position   0
   y Paned Position   0
   _

   cursor

   The cursor to use when the mouse pointer is over the Paned
   widget, but not in any of its children (children may also
   inherit this cursor). It should be noted that the internal
   borders are actually part of the Paned widget, not the
   children.

   gripCursor

   The cursor to use when the grips are not active. The default
   value is verticalGripCursor or horizontalGripCursor depending
   on the orientation of the Paned widget.

   gripIndent

   The amount of space left between the right (or bottom) edge of
   the Paned widget and all the grips.

   gripTranslation

   Translation table that will be applied to all grips.

   horizontalBetweenCursor

   verticalBetweenCursor

   The cursor to be used for the grip when changing the boundary
   between two panes. These resources allow the cursors to be
   different depending on the orientation of the Paned widget.

   horizontalGripCursor

   verticalGripCursor

   The cursor to be used for the grips when they are not active.
   These resources allow the cursors to be different depending on
   the orientation of the Paned widget.

   internalBorderColor

   A pixel value which indexes the widget's colormap to derive the
   internal border color of the widget's window. The class name of
   this resource allows Paned*BorderColor: blue to set the
   internal border color for the Paned widget. An optimization is
   invoked if internalBorderColor and background are the same, and
   the internal borders are not drawn. internalBorderWidth is
   still left between the panes, however.

   internalBorderWidth

   The width of the internal borders. This is the amount of space
   left between the panes. The class name of this resource allows
   Paned*BorderWidth: 3 to set the internal border width for the
   Paned widget.

   leftCursor

   rightCursor

   The cursor used to indicate which is the important pane to
   resize when the Paned widget is oriented horizontally.

   lowerCursor

   upperCursor

   The cursor used to indicate which is the important pane to
   resize when the Paned widget is oriented vertically. This is
   not the same as the number of panes, since this also contains a
   grip for some of the panes, use XawPanedGetNumSub to retrieve
   the number of panes.

   orientation

   The orientation to stack the panes. This value can be either
   XtorientVertical or XtorientHorizontal.

   refigureMode

   This resource allows pane layout to be suspended. If this value
   is False, then no layout actions will be taken. This may
   improve efficiency when adding or removing more than one pane
   from the Paned widget.

Constraint Resources

   Each child of the Paned widget may request special layout
   resources be applied to it. These constraint resources allow
   the Paned widget's children to specify individual layout
   requirements.

         Name              Class         Type    Notes  Default Value
      allowResize         Boolean       Boolean             False
          max               Max        Dimension          Infinity
          min               Min        Dimension       Height of Grips
   preferredPaneSize PreferredPaneSize Dimension          ask child
   resizeToPreferred      Boolean       Boolean             False
       showGrip          ShowGrip       Boolean             True
      skipAdjust          Boolean       Boolean             False
           _

   allowResize

   If this value is False the the Paned widget will disallow all
   geometry requests from this child.

   max

   min

   The absolute maximum or minimum size for this pane. These
   values will never be overridden by the Paned widget. This may
   cause some panes to be pushed off the bottom (or right) edge of
   the paned widget.

   preferredPaneSize

   Normally the paned widget makes a QueryGeometry call on a child
   to determine the preferred size of the child's pane. There are
   times when the application programmer or the user has a better
   idea of the preferred size of a pane. Setting this resource
   causes the value passed to be interpreted as the preferred
   size, in pixels, of this pane.

   resizeToPreferred

   Determines whether or not to resize each pane to its preferred
   size when the Paned widget is resized. See Layout Semantics for
   details.

   showGrip

   If True then a grip will be shown for this pane. The grip
   associated with a pane is either below or to the right of the
   pane. No grip is ever shown for the last pane.

   skipAdjust

   This resource is used to determine which pane is forced to be
   resized. Setting this value to True makes this pane less likely
   to be forced to be resized. See Layout Semantics for details.

Layout Semantics

   In order to make effective use of the Paned widget it is
   helpful to know the rules it uses to determine which child will
   be resized in any given situation. There are three rules used
   to determine which child is resized. While these rules are
   always the same, the panes that are searched can change
   depending upon what caused the relayout.

   Layout Rules

   1

   Do not let a pane grow larger than its max or smaller than its
   min.

   2

   Do not adjust panes with skipAdjust set.

   3

   Do not adjust panes away from their preferred size, although
   moving one closer to its preferred size is fine.

   When searching the children the Paned widget looks for panes
   that satisfy all the rules, and if unsuccessful then it
   eliminates rule 3 and then 2. Rule 1 is always enforced.

   If the relayout is due to a resize or change in management then
   the panes are searched from bottom to top. If the relayout is
   due to grip movement then they are searched from the grip
   selected in the direction opposite the pane selected.

Resizing Panes from a Grip Action

   The pane above the grip is resized by invoking the GripAction
   with UpLeftPane specified. The panes below the grip are each
   checked against all rules, then rules 2 and 1 and finally
   against rule 1 only. No pane above the chosen pane will ever be
   resized.

   The pane below the grip is resized by invoking the GripAction
   with LowRightPane specified. The panes above the grip are each
   checked in this case. No pane below the chosen pane will ever
   be resized.

   Invoking GripAction with ThisBorderOnly specified just moves
   the border between the panes. No other panes are ever resized.

Resizing Panes after the Paned widget is resized.

   When the Pane widget is resized it must determine a new size
   for each pane. There are two methods of doing this. The Paned
   widget can either give each pane its preferred size and then
   resize the panes to fit, or it can use the current sizes and
   then resize the panes to fit. The resizeToPreferred resource
   allows the application to tell the Paned widget whether to
   query the child about its preferred size (subject to the the
   preferredPaneSize) or to use the current size when refiguring
   the pane locations after the pane has been resized.

   There is one special case. All panes assume they should resize
   to their preferred size until the Paned widget becomes visible
   to the user.

Managing Children and Geometry Management

   The Paned widget always resizes its children to their preferred
   sizes when a new child is managed, or a geometry management
   request is honored. The Paned widget will first attempt to
   resize itself to contain its panes exactly. If this is not
   possible then it will hunt through the children, from bottom to
   top (right to left), for a pane to resize.

Special Considerations

   When a user resizes a pane with the grips, the Paned widget
   assumes that this new size is the preferred size of the pane.

Grip Translations

   The Paned widget has no action routines of its own, as all
   actions are handled through the grips. The grips are each
   assigned a default Translation table.



        <Btn1Down>:     GripAction(Start, UpLeftPane)

        <Btn2Down>:     GripAction(Start, ThisBorderOnly)
        <Btn3Down>:     GripAction(Start, LowRightPane)
        <Btn1Motion>:   GripAction(Move, UpLeftPane)
        <Btn2Motion>:   GripAction(Move, ThisBorderOnly)
        <Btn3Motion>:   GripAction(Move, LowRightPane)
        Any<BtnUp>:     GripAction(Commit)

   The Paned widget interprets the GripAction as taking two
   arguments. The first argument may be any of the following:

   Start

   Sets up the Paned widget for resizing and changes the cursor of
   the grip. The second argument determines which pane will be
   resized, and can take on any of the three values shown above.

   Move

   The internal borders are drawn over the current pane locations
   to animate where the borders would actually be placed if you
   were to move this border as shown. The second argument must
   match the second argument that was passed to the Start action,
   that began this process. If these arguments are not passed, the
   behavior is undefined.

   Commit

   This argument causes the Paned widget to commit the changes
   selected by the previously started action. The cursor is
   changed back to the grip's inactive cursor. No second argument
   is needed in this case.

Convenience Routines

   To enable or disable a child's request for pane resizing, use
   XawPanedAllowResize :

   voidfsfunc XawPanedAllowResize(Widget w, Boolean allow_resize);

   w

   Specifies the child pane.

   allow_resize

   Specifies whether or not resizing requests for this child will
   be granted by the Paned widget.

   If allow_resize is True, the Paned widget allows geometry
   requests from the child to change the pane's height. If
   allow_resize is False, the Paned widget ignores geometry
   requests from the child to change the pane's height. The
   default state is True before the Pane is realized and False
   after it is realized. This procedure is equivalent to changing
   the allowResize constraint resource for the child.

   To change the minimum and maximum height settings for a pane,
   use XawPanedSetMinMax :

   voidfsfunc XawPanedSetMinMax(Widget w, intmin, max);

   w

   Specifies the child pane.

   min

   Specifies the new minimum height of the child, expressed in
   pixels.

   max

   Specifies new maximum height of the child, expressed in pixels.

   This procedure is equivalent to setting the min and max
   constraint resources for the child.

   To retrieve the minimum and maximum height settings for a pane,
   use XawPanedGetMinMax :

   voidfsfunc XawPanedGetMinMax(Widget w, int*min_return,
   *max_return);

   w

   Specifies the child pane.

   min_return

   Returns the minimum height of the child, expressed in pixels.

   max_return

   Returns the maximum height of the child, expressed in pixels.

   This procedure is equivalent to getting the min and max
   resources for this child child.

   To enable or disable automatic recalculation of pane sizes and
   positions, use XawPanedSetRefigureMode :

   voidfsfunc XawPanedSetRefigureMode(Widget w, Boolean mode);

   w

   Specifies the Paned widget.

   mode

   Specifies whether the layout of the Paned widget is enabled
   (True) or disabled (False).

   When making several changes to the children of a Paned widget
   after the Paned has been realized, it is a good idea to disable
   relayout until after all changes have been made.

   To retrieve the number of panes in a paned widget use
   XawPanedGetNumSub:

   intfsfunc XawPanedGetNumSub(Widget w);

   w

   Specifies the Paned widget.

   This function returns the number of panes in the Paned widget.
   This is not the same as the number of children, since the grips
   are also children of the Paned widget.

Porthole Widget




Application Header file <X11/Xaw/Porthole.h>

Class Header file       <X11/Xaw/PortholeP.h>

Class           portholeWidgetClass

Class Name      Porthole

Superclass      Composite


   The Porthole widget provides geometry management of a list of
   arbitrary widgets, only one of which may be managed at any
   particular time. The managed child widget is reparented within
   the porthole and is moved around by the application (typically
   under the control of a Panner widget).

Resources

   When creating a Porthole widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A see Layout Semantics
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   reportCallback ReportCallback Callback   NULL
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0
   _

   reportCallback

   A list of functions to invoke whenever the managed child widget
   changes size or position.

Layout Semantics

   The Porthole widget allows its managed child to request any
   size that is as large or larger than the Porthole itself and
   any location so long as the child still obscures all of the
   Porthole. This widget typically is used with a Panner widget.

Porthole Callbacks

   The functions registered on the reportCallback list are invoked
   whenever the managed child changes size or position:

   voidfsfunc ReportProc(Widget porthole, XtPointer client_data,
   XtPointer report);

   porthole

   Specifies the Porthole widget.

   client_data

   Specifies the client data.

   report

   Specifies a pointer to an XawPannerReport structure containing
   the location and size of the slider and the size of the canvas.

Tree Widget

Application Header file <X11/Xaw/Tree.h>
Class Header file       <X11/Xaw/TreeP.h>
Class           treeWidgetClass
Class Name      Tree
Superclass      Constraint

   The Tree widget provides geometry management of arbitrary
   widgets arranged in a directed, acyclic graph (i.e., a tree).
   The hierarchy is constructed by attaching a constraint resource
   called treeParent to each widget indicating which other node in
   the tree should be treated as the widget's superior. The
   structure of the tree is shown by laying out the nodes in the
   standard format for tree diagrams with lines drawn connecting
   each node with its children.

   The Tree sizes itself according to the needs of its children
   and is not intended to be resized by its parent. Instead, it
   should be placed inside another composite widget (such as the
   Porthole or Viewport) that can be used to scroll around in the
   tree.

Resources

   When creating a Tree widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoReconfigure AutoReconfigure Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   gravity Gravity XtGravity   WestGravity
   height Height Dimension A see Layout Semantics
   hSpace HSpace Dimension   4
   lineWidth LineWidth Dimension   0
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   vSpace VSpace Dimension   4
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0

   autoReconfigure

   Whether or not to layout the tree every time a node is added or
   removed.

   gravity

   Specifies the side of the widget from which the tree should
   grow. Valid values include WestGravity, NorthGravity,
   EastGravity, and SouthGravity.

   hSpace

   vSpace

   The amount of space, in pixels, to leave between the children.
   This resource specifies the amount of space left between the
   outermost children and the edge of the box.

   lineWidth

   The width of the lines from nodes that do not have a treeGC
   constraint resource to their children.

Constraint Resources

   Each child of the Tree widget must specify its superior node in
   the tree. In addition, it may specify a GC to use when drawing
   a line between it and its inferior nodes.
      Name      Class     Type  Notes Default Value
     treeGC     TreeGC     GC             NULL
   treeParent TreeParent Widget           NULL

   treeGC

   This specifies the GC to use when drawing lines between this
   widget and its inferiors in the tree. If this resource is not
   specified, the Tree's foreground and lineWidth will be used.

   treeParent

   This specifies the superior node in the tree for this widget.
   The default is for the node to have no superior (and to
   therefore be at the top of the tree).

Layout Semantics

   Each time a child is managed or unmanaged, the Tree widget will
   attempt to reposition the remaining children to fix the shape
   of the tree if the resource is set. Children at the top (most
   superior) of the tree are drawn at the side specified by the
   resource.

   After positioning all children, the Tree widget attempts to
   shrink its own size to the minimum dimensions required for the
   layout.

Convenience Routines

   The most efficient way to layout a tree is to set
   autoReconfigure to False and then use the XawTreeForceLayout
   routine to arrange the children.

   voidfsfunc XawTreeForceLayout(Widget w);

   w

   Specifies the Tree widget.

Viewport Widget




Application Header file <X11/Xaw/Viewport.h>

Class Header file       <X11/Xaw/ViewportP.h>

Class           viewportWidgetClass

Class Name      Viewport

Superclass      Form


   The Viewport widget consists of a frame window, one or two
   Scrollbars, and an inner window. The size of the frame window
   is determined by the viewing size of the data that is to be
   displayed and the dimensions to which the Viewport is created.
   The inner window is the full size of the data that is to be
   displayed and is clipped by the frame window. The Viewport
   widget controls the scrolling of the data directly. No
   application callbacks are required for scrolling.

   When the geometry of the frame window is equal in size to the
   inner window, or when the data does not require scrolling, the
   Viewport widget automatically removes any scrollbars. The
   forceBars option causes the Viewport widget to display all
   scrollbars permanently.

Resources

   When creating a Viewport widget instance, the following
   resources are retrieved from the argument list or the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   allowHoriz Boolean Boolean   False
   allowVert Boolean Boolean   False
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   forceBars Boolean Boolean   False
   height Height Dimension   height of the child
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   reportCallback ReportCallback XtCallbackList   NULL
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   useBottom Boolean Boolean   False
   useRight Boolean Boolean   False
   width Width Dimension   width of the child
   x Position Position   0
   y Position Position   0
   _

   allowHoriz

   allowVert

   If these resources are False then the Viewport will never
   create a scrollbar in this direction. If it is True then the
   scrollbar will only appear when it is needed, unless forceBars
   is True.

   forceBars

   When True the scrollbars that have been allowed will always be
   visible on the screen. If False the scrollbars will be visible
   only when the inner window is larger than the frame.

   reportCallback

   These callbacks will be executed whenever the Viewport adjusts
   the viewed area of the child. The call_data parameter is a
   pointer to an XawPannerReport structure.

   useBottom

   useRight

   By default the scrollbars appear on the left and top of the
   screen. These resources allow the vertical scrollbar to be
   placed on the right edge of the Viewport, and the horizontal
   scrollbar on the bottom edge of the Viewport.

Layout Semantics

   The Viewport widget manages a single child widget. When the
   size of the child is larger than the size of the Viewport, the
   user can interactively move the child within the Viewport by
   repositioning the scrollbars.

   The default size of the Viewport before it is realized is the
   width and/or height of the child. After it is realized, the
   Viewport will allow its child to grow vertically or
   horizontally if allowVert or allowHoriz are set, respectively.
   If the corresponding vertical or horizontal scrollbar is not
   enabled, the Viewport will propagate the geometry request to
   its own parent and the child will be allowed to change size
   only if the Viewport's parent allows it. Regardless of whether
   or not scrollbars are enabled in the corresponding direction,
   if the child requests a new size smaller than the Viewport
   size, the change will be allowed only if the parent of the
   Viewport allows the Viewport to shrink to the appropriate
   dimension.

   The scrollbar children of the Viewport are named horizontal and
   vertical. By using these names the programmer can specify
   resources for the individual scrollbars. XtSetValues can be
   used to modify the resources dynamically once the widget ID has
   been obtained with XtNameToWidget.

Note

   Although the Viewport is a Subclass of the Form, no resources
   for the Form may be supplied for any of the children of the
   Viewport. These constraints are managed internally and are not
   meant for public consumption.

Chapter 7. Creating New Widgets (Subclassing)

   Table of Contents

   Public Header File
   Private Header File
   Widget Source File

   Although the task of creating a new widget may at first appear
   a little daunting, there is a basic simple pattern that all
   widgets follow. The Athena Widget library contains a special
   widget called the Template widget that is intended to assist
   the novice widget programmer in writing a custom widget.

   Reasons for wishing to write a custom widget include:
     * Providing a graphical interface not currently supported by
       any existing widget set.
     * Convenient access to resource management procedures to
       obtain fonts, colors, etc., even if user customization is
       not desired.
     * Convenient access to user input dispatch and translation
       management procedures.
     * Access to callback mechanism for building higher-level
       application libraries.
     * Customizing the interface or behavior of an existing widget
       to suit a special application need.
     * Desire to allow user customization of resources such as
       fonts, colors, etc., or to allow convenient re-binding of
       keys and buttons to internal functions.
     * Converting a non-Toolkit application to use the Toolkit.

   In each of these cases, the operation needed to create a new
   widget is to "subclass" an existing one. If the desired
   semantics of the new widget are similar to an existing one,
   then the implementation of the existing widget should be
   examined to see how much work would be required to create a
   subclass that will then be able to share the existing class
   methods. Much time will be saved in writing the new widget if
   an existing widget class Expose, Resize and/or GeometryManager
   method can be used by the subclass.

   Note that some trivial uses of a ``bare-bones'' widget may be
   achieved by simply creating an instance of the Core widget. The
   class variable to use when creating a Core widget is
   widgetClass. The geometry of the Core widget is determined
   entirely by the parent widget.

   It is very often the case than an application will have a
   special need for a certain set of functions and that many
   copies of these functions will be needed. For example, when
   converting an older application to use the Toolkit, it may be
   desirable to have a "Window Widget" class that might have the
   following semantics:
     * Allocate 2 drawing colors in addition to a background
       color.
     * Allocate a text font.
     * Execute an application-supplied function to handle exposure
       events.
     * Execute an application-supplied function to handle user
       input events.

   It is obvious that a completely general-purpose
   WindowWidgetClass could be constructed that would export all
   class methods as callbacks lists, but such a widget would be
   very large and would have to choose some arbitrary number of
   resources such as colors to allocate. An application that used
   many instances of the general-purpose widget would therefore
   un-necessarily waste many resources.

   In this section, an outline will be given of the procedure to
   follow to construct a special-purpose widget to address the
   items listed above. The reader should refer to the appropriate
   sections of the X Toolkit Intrinsics - C Language Interface for
   complete details of the material outlined here. Section 1.4 of
   the Intrinsics should be read in conjunction with this section.

   All Athena widgets have three separate files associated with
   them:
     * A "public" header file containing declarations needed by
       applications programmers
     * A "private" header file containing additional declarations
       needed by the widget and any subclasses
     * A source code file containing the implementation of the
       widget

   This separation of functions into three files is suggested for
   all widgets, but nothing in the Toolkit actually requires this
   format. In particular, a private widget created for a single
   application may easily combine the "public" and "private"
   header files into a single file, or merge the contents into
   another application header file. Similarly, the widget
   implementation can be merged into other application code.

   In the following example, the public header file <
   X11/Xaw/Template.h >, the private header file <
   X11/Xaw/TemplateP.h > and the source code file <
   X11/Xaw/Template.c > will be modified to produce the
   "WindowWidget" described above. In each case, the files have
   been designed so that a global string replacement of "Template"
   and "template" with the name of your new widget, using the
   appropriate case, can be done.

Public Header File

   The public header file contains declarations that will be
   required by any application module that needs to refer to the
   widget; whether to create an instance of the class, to perform
   an XtSetValues operation, or to call a public routine
   implemented by the widget class.

   The contents of the Template public header file, <
   X11/Xaw/Template.h >, are:
..


/* Copyright (c) X Consortium 1987, 1988 */

#ifndef _Template_h
#define _Template_h

/****************************************************************
 *
 * Template widget
 *
 ****************************************************************/

/* Resources:

 Name   Class           RepType Default Value
 ----           -----           ------- -------------
 background     Background              Pixel   XtDefaultBackground
 border BorderColor             Pixel   XtDefaultForeground
 borderWidth    BorderWidth             Dimension       1
 destroyCallback        Callback                Pointer NULL
 height Height          Dimension       0
 mappedWhenManaged      MappedWhenManaged       Boolean True
 sensitive      Sensitive               Boolean True
 width  Width           Dimension       0
 x              Position                Position        0
 y              Position                Position        0

*/

/* define any special resource names here that are not in <X11/StringDef
s.h> */

#define XtNtemplateResource "templateResource"

#define XtCTemplateResource "TemplateResource"

/* declare specific TemplateWidget class and instance datatypes */

typedef struct _TemplateClassRec*       TemplateWidgetClass;
typedef struct _TemplateRec*    TemplateWidget;

/* declare the class constant */

extern WidgetClass templateWidgetClass;

#endif /* _Template_h */


   You will notice that most of this file is documentation. The
   crucial parts are the last 8 lines where macros for any private
   resource names and classes are defined and where the widget
   class datatypes and class record pointer are declared.

   For the "WindowWidget", we want 2 drawing colors, a callback
   list for user input and an exposeCallback callback list, and we
   will declare three convenience procedures, so we need to add



/* Resources:
        ...
 callback       Callback        Callback        NULL
 drawingColor1  Color   Pixel           XtDefaultForeground
 drawingColor2  Color   Pixel           XtDefaultForeground
 exposeCallback Callback        Callback        NULL
 font           Font    XFontStruct*    XtDefaultFont
        ...
 */

#define XtNdrawingColor1 "drawingColor1"
#define XtNdrawingColor2 "drawingColor2"
#define XtNexposeCallback "exposeCallback"

extern Pixel WindowColor1(\|/* Widget */\|);
extern Pixel WindowColor2(\|/* Widget */\|);
extern Font\ \ WindowFont(\|/* Widget */\|);


   Note that we have chosen to call the input callback list by the
   generic name, callback, rather than a specific name. If widgets
   that define a single user-input action all choose the same
   resource name then there is greater possibility for an
   application to switch between widgets of different types.

Private Header File

   The private header file contains the complete declaration of
   the class and instance structures for the widget and any
   additional private data that will be required by anticipated
   subclasses of the widget. Information in the private header
   file is normally hidden from the application and is designed to
   be accessed only through other public procedures; e.g.
   XtSetValues .

   The contents of the Template private header file, <
   X11/Xaw/TemplateP.h >, are:
/* Copyright (c) X Consortium 1987, 1988
 */

#ifndef _TemplateP_h
#define _TemplateP_h

#include <X11/Xaw/Template.h>
/* include superclass private header file */
#include <X11/CoreP.h>

/* define unique representation types not found in <X11/StringDefs.h> */

#define XtRTemplateResource "TemplateResource"

typedef struct {
        int empty;
} TemplateClassPart;

typedef struct _TemplateClassRec {
        CoreClassPart   core_class;
        TemplateClassPart       template_class;
} TemplateClassRec;

extern TemplateClassRec templateClassRec;

typedef struct {
        /* resources */
        char* resource;
        /* private state */
} TemplatePart;

typedef struct _TemplateRec {
        CorePart        core;
        TemplatePart    template;
} TemplateRec;

#endif /* _TemplateP_h */


   The private header file includes the private header file of its
   superclass, thereby exposing the entire internal structure of
   the widget. It may not always be advantageous to do this; your
   own project development style will dictate the appropriate
   level of detail to expose in each module.

   The "WindowWidget" needs to declare two fields in its instance
   structure to hold the drawing colors, a resource field for the
   font and a field for the expose and user input callback lists:
typedef struct {
        /* resources */
        Pixel color_1;
        Pixel color_2;
        XFontStruct* font;
        XtCallbackList expose_callback;
        XtCallbackList input_callback;
        /* private state */
        /* (none) */
} WindowPart;

Widget Source File

   The source code file implements the widget class itself. The
   unique part of this file is the declaration and initialization
   of the widget class record structure and the declaration of all
   resources and action routines added by the widget class.

   The contents of the Template implementation file, <
   X11/Xaw/Template.c >, are:
/* Copyright (c) X Consortium 1987, 1988
 */

#include <X11/IntrinsicP.h>
#include <X11/StringDefs.h>
#include "TemplateP.h"

static XtResource resources[] = {
#define offset(field) XtOffsetOf(TemplateRec, template.field)
        /* {name, class, type, size, offset, default_type, default_addr}
, */
    { XtNtemplateResource, XtCTemplateResource, XtRTemplateResource,
          sizeof(char*), offset(resource), XtRString, (XtPointer) "defau
lt" },
#undef offset
};

static void TemplateAction(/* Widget, XEvent*, String*, Cardinal* */);

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"template",    TemplateAction},
};

static char translations[] =
"       <Key>:  template(\|) \\n\\
";

TemplateClassRec templateClassRec = {
  { /* core fields */
        /* superclass   */      (WidgetClass) &widgetClassRec,
        /* class_name   */      "Template",
        /* widget_size  */      sizeof(TemplateRec),
        /* class_initialize     */      NULL,
        /* class_part_initialize        */      NULL,
        /* class_inited */      FALSE,
        /* initialize   */      NULL,
        /* initialize_hook      */      NULL,
        /* realize      */      XtInheritRealize,
        /* actions      */      actions,
        /* num_actions  */      XtNumber(actions),
        /* resources    */      resources,
        /* num_resources        */      XtNumber(resources),
        /* xrm_class    */      NULLQUARK,
        /* compress_motion      */      TRUE,
        /* compress_exposure    */      TRUE,
        /* compress_enterleave */       TRUE,
        /* visible_interest     */      FALSE,
        /* destroy      */      NULL,
        /* resize       */      NULL,
        /* expose       */      NULL,
        /* set_values   */      NULL,
        /* set_values_hook      */      NULL,
        /* set_values_almost    */      XtInheritSetValuesAlmost,
        /* get_values_hook      */      NULL,
        /* accept_focus */      NULL,
        /* version      */      XtVersion,
        /* callback_private     */      NULL,
        /* tm_table     */      translations,
        /* query_geometry       */      XtInheritQueryGeometry,
        /* display_accelerator  */      XtInheritDisplayAccelerator,
        /* extension    */      NULL
  },
  { /* template fields */
        /* empty        */      0
  }
};

WidgetClass templateWidgetClass = (WidgetClass)&templateClassRec;

   The resource list for the "WindowWidget" might look like the
   following:
static XtResource resources[] = {
#define offset(field) XtOffsetOf(WindowWidgetRec, window.field)
        /* {name, class, type, size, offset, default_type, default_addr}
, */
        { XtNdrawingColor1, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_1), XtRString, XtDefaultForeground },
        { XtNdrawingColor2, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_2), XtRString, XtDefaultForeground },
        { XtNfont, XtCFont, XtRFontStruct, sizeof(XFontStruct*),
                  offset(font), XtRString, XtDefaultFont },
        { XtNexposeCallback, XtCCallback, XtRCallback, sizeof(XtCallback
List),
                  offset(expose_callback), XtRCallback, NULL },
        { XtNcallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
                  offset(input_callback), XtRCallback, NULL },
#undef offset
};

   The user input callback will be implemented by an action
   procedure which passes the event pointer as call_data. The
   action procedure is declared as:
/* ARGSUSED */
static void InputAction(w, event, params, num_params)
        Widget w;
        XEvent *event;
        String *params;         /* unused */
        Cardinal *num_params;   /* unused */
{
        XtCallCallbacks(w, XtNcallback, (XtPointer)event);
}

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"input",       InputAction},
};

   and the default input binding will be to execute the input
   callbacks on KeyPress and ButtonPress :
static char translations[] =
"       <Key>:  input(\|) \\n\\
        <BtnDown>:      input(\|) \\
";

   In the class record declaration and initialization, the only
   field that is different from the Template is the expose
   procedure:
/* ARGSUSED */
static void Redisplay(w, event, region)
        Widget w;
        XEvent *event;  /* unused */
        Region region;
{
        XtCallCallbacks(w, XtNexposeCallback, (XtPointer)region);
}

WindowClassRec windowClassRec = {

        ...

        /* expose       */      Redisplay,

   The "WindowWidget" will also declare three public procedures to
   return the drawing colors and the font id, saving the
   application the effort of constructing an argument list for a
   call to XtGetValues :
Pixel WindowColor1(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_1;
}

Pixel WindowColor2(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_2;
}

Font WindowFont(w)
        Widget w;
{
        return ((WindowWidget)w)->window.font->fid;
}

   The "WindowWidget" is now complete. The application can
   retrieve the two drawing colors from the widget instance by
   calling either XtGetValues , or the WindowColor functions. The
   actual window created for the "WindowWidget" is available by
   calling the XtWindow function.

Chapter 8. Acknowledgments

   Many thanks go to Ralph Swick (Project Athena / Digital) who
   has contributed much time and effort to this widget set.
   Previous versions of the widget set are largely due to his time
   and effort. Many of the improvements that I have been able to
   make are because he provided a solid foundation to build upon.
   While much of the effort has been Ralph's, many other people
   have contributed to the code.
Mark Ackerman (formerly Project Athena)
Donna Converse (MIT X Consortium)
Jim Fulton (formerly MIT X Consortium)
Loretta Guarino-Reid (Digital WSL)
Charles Haynes (Digital WSL)
Rich Hyde (Digital WSL)
Mary Larson (Digital UEG)
Joel McCormack (Digital WSL)
Ron Newman (formerly Project Athena)
Jeanne Rich (Digital WSL)
Terry Weissman (formerly Digital WSL)

   While not much remains of the X10 toolkit, many of the ideas
   for this widget set come from that original version. The design
   and implementation of the X10 toolkit were done by:
Mike Gancarz (formerly Digital UEG)
Charles Haynes (Digital WSL)
Phil Karlton (formerly Digital WSL)
Kathleen Langone (Digital UEG)
Mary Larson (Digital UEG)
Ram Rao (Digital UEG)
Smokey Wallace (formerly Digital WSL)
Terry Weissman (formerly Digital WSL)

   I have used the formatting ideas, and some of the words from
   previous versions of this document. The X11R3 Athena widget
   document was written by:
Ralph R. Swick (Project Athena/ Digital)
Terry Weissman (formerly Digital WSL)
Al Mento (Digital UEG)

   Putting this manual together was a major task in and of itself.
   I would like to thank Ralph Swick, Donna Converse, and Jim
   Fulton for taking the time to help convert my technical
   knowledge into legible text. A special thanks to Jean Diaz
   (O'Reilly and Associates) for spending nearly a month with me
   working out all the annoying little details.
Chris D. Peterson
MIT X Consortium 1989

   The R5 edition of this document has been edited by the research
   staff of the MIT X Consortium, with significant contributions
   by Jim Fulton (NCD).
Donna Converse
MIT X Consortium 1991

   The R6 edition of this document has been edited to reflect
   changes brought about by research staff of the Omron
   Corporation, with special recognition to Li Yuhong, Seiji
   Kuwari, and Hiroshi Kuribayashi for the X11R5/contrib/lib/Xaw
   internationalization that inspired this version.
Frank Sheeran
Omron Corporation 1994
