XT FUNCTIONS XtClass(3xt)
NAME
XtClass, XtSuperclass, XtIsSubclass, XtCheckSubclass, XtIs-
Object, XtIsRectObj, XtIsWidget, XtIsComposite, XtIs-
Constraint, XtIsShell, XtIsOverrideShell, XtIsWMShell, XtIsVendorShell, XtIsTransientShell, XtIsTopLevelShell,XtIsApplicationShell, XtIsSessionShell - obtain and verify a
widget's class SYNTAXcc [ flag... ] file... -lXt [ library... ]
WidgetClass XtClass(Widget w);
WidgetClass XtSuperclass(Widget w);Boolean XtIsSubclass(Widget w, WidgetClass widget_class);
void XtCheckSubclass(Widget widget, WidgetClasswidget_class, String message);
Boolean XtIsObject(Widget w); Boolean XtIsRectObj(Widget w); Boolean XtIsWidget(Widget w); Boolean XtIsComposite(Widget w); Boolean XtIsConstraint(Widget w, Boolean XtIsShell(Widget w); Boolean XtIsOverrideShell(Widget w); Boolean XtIsWMShell(Widget w); Boolean XtIsVendorShell(Widget w); Boolean XtIsTransientShell(Widget w); Boolean XtIsTopLevelShell(Widget w); Boolean XtIsApplicationShell(Widget w); Boolean XtIsSessionShell(Widget w); ARGUMENTS w Specifies the widget.widget_class
Specifies the widget class. X Version 11 Last change: libXt 1.0.8 1XT FUNCTIONS XtClass(3xt)
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 thespecified widget is equal to or is a subclass of the speci-
fied class. The widget's class can be any number of subc-
lasses down the chain and need not be an immediate subclassof the specified class. Composite widgets that need to res-
trict the class of the items they contain can use XtIsSub-
class to find out if a widget belongs to the desired class of objects. The XtCheckSubclass macro determines if the class of thespecified widget is equal to or is a subclass of the speci-
fied widget class. The widget can be any number of subc-
lasses 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 anIntrinsics-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, XtIs-
OverrideShell, XtIsWMShell, XtIsVendorShell, XtIsTransient-
Shell, XtIsTopLevelShell, XtIsApplicationShell, and XtIsSes-
sionShell. TheSEE ALSO
XtAppErrorMsg(3Xt), XtDisplay(3Xt)X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface
X Version 11 Last change: libXt 1.0.8 2XT FUNCTIONS XtClass(3xt)
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:__________________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|___________________________________|
| Availability | x11/library/toolkit/libxt ||_____________________________|___________________________________|
| Interface Stability | Committed ||_____________________________|___________________________________|
| MT-Level | See XtToolkitThreadInitialize(3XT)|
|_____________________________|___________________________________|
X Version 11 Last change: libXt 1.0.8 3