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Alphabetical listing for X

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XtClass(3Xt)
X11R6
NAME
  XtClass, XtSuperclass, XtIsSubclass, XtCheckSubclass, XtIsObject,
  XtIsRectObj, XtIsWidget, XtIsComposite, XtIsConstraint, XtIsShell,
  XtIsOverrideShell, XtIsWMShell, XtIsVendorShell, XtIsTransientShell,
  XtIsTopLevelShell, XtIsApplicationShell, XtIsSessionShell - obtain and
  verify a widget's class

SYNOPSIS
  WidgetClass XtClass(w)
	  Widget w;

  WidgetClass XtSuperclass(w)
	  Widget w;

  Boolean XtIsSubclass(w, widget_class)
	  Widget w;
	  WidgetClass widget_class;

  void XtCheckSubclass(widget, widget_class, message)
	  Widget widget;
	  WidgetClass widget_class;
	  String message;

  Boolean XtIsObject(w)
	  Widget w;

  Boolean XtIsRectObj(w)
	  Widget w;

  Boolean XtIsWidget(w)
	  Widget w;

  Boolean XtIsComposite(w)
	  Widget w;

  Boolean XtIsConstraint(w)
	  Widget w;

  Boolean XtIsShell(w)
	  Widget w;

  Boolean XtIsOverrideShell(w)
	  Widget w;

  Boolean XtIsWMShell(w)
	  Widget w;

  Boolean XtIsVendorShell(w)
	  Widget w;

  Boolean XtIsTransientShell(w)
	  Widget w;

  Boolean XtIsTopLevelShell(w)
	  Widget w;

  Boolean XtIsApplicationShell(w)
	  Widget w;

  Boolean XtIsSessionShell(w)
	  Widget w;

ARGUMENTS
  w   Specifies the widget.

  widget_class
      Specifies the widget class.

  message
      Specifies the message that is to be used.

DESCRIPTION
  The XtClass function returns a pointer to the widget's class structure.

  The XtSuperclass function returns a pointer to the widget's superclass
  class structure.

  The XtIsSubclass function returns True if the class of the specified widget
  is equal to or is a subclass of the specified class. The widget's class can
  be any number of subclasses down the chain and need not be an immediate
  subclass of the specified class. Composite widgets that need to restrict
  the class of the items they contain can use XtIsSubclass to find out if a
  widget belongs to the desired class of objects.

  The XtCheckSubclass macro determines if the class of the specified widget
  is equal to or is a subclass of the specified widget class. The widget can
  be any number of subclasses down the chain and need not be an immediate
  subclass of the specified widget class. If the specified widget is not a
  subclass, XtCheckSubclass constructs an error message from the supplied
  message, the widget's actual class, and the expected class and calls
  XtErrorMsg.  XtCheckSubclass should be used at the entry point of exported
  routines to ensure that the client has passed in a valid widget class for
  the exported operation.

  XtCheckSubclass is only executed when the widget has been compiled with the
  compiler symbol DEBUG defined; otherwise, it is defined as the empty string
  and generates no code.

  To test if a given widget belongs to a subclass of an Intrinsics-defined
  class, the Intrinsics defines macros or functions equivalent to
  XtIsSubclass for each of the built-in classes. These procedures are
  XtIsObject, XtIsRectObj, XtIsWidget, XtIsComposite, XtIsConstraint,
  XtIsShell, XtIsOverrideShell, XtIsWMShell, XtIsVendorShell,
  XtIsTransientShell, XtIsTopLevelShell, XtIsApplicationShell, and
  XtIsSessionShell.

SEE ALSO
  XtAppErrorMsg(3Xt), XtDisplay(3Xt)

  X Toolkit Intrinsics -- C Language Interface

  Xlib -- C Language X Interface

Index for Section 3Xt

Alphabetical listing for X

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