XtClass(3Xt) X11R5 XtClass(3Xt)NAME
XtClass, XtSuperclass, XtIsSubclass, XtCheckSubclass, XtIsComposite,
XtIsManaged - obtain and verify a widget's class
SYNTAX
WidgetClass XtClass(w)
Widget w;
WidgetClass XtSuperclass(w)
Widget w;
Boolean XtIsSubclass(w, widget_class)
Widget w;
WidgetClass widget_class;
void XtCheckSubclass(w, widget_class, message)
Widget w;
WidgetClass widget_class;
String message;
Boolean XtIsComposite(w)
Widget w;
Boolean XtIsManaged(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 function returns a pointer to the widget's class structure.
The function returns a pointer to the widget's superclass class struc‐
ture.
The function returns if the class of the specified widget is equal to
or is a subclass of the specified widget class. The specified widget
can be any number of subclasses down the chain and need not be an imme‐
diate subclass of the specified widget class. Composite widgets that
need to restrict the class of the items they contain can use to find
out if a widget belongs to the desired class of objects.
The 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 sub‐
class of the specified widget class. If the specified widget is not a
subclass, constructs an error message from the supplied message, the
widget's actual class, and the expected class and calls 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.
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.
The function is a convenience function that is equivalent to with spec‐
ified.
The macro (for widget programmers) or function (for application pro‐
grammers) returns if the specified child widget is managed or if it is
not.
SEE ALSOXtAppErrorMsg(3Xt), XtDisplay(3Xt)
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface
XtClass(3Xt)