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XtInsertEventTypeHandler(3)	 XT FUNCTIONS	   XtInsertEventTypeHandler(3)

NAME
       XtInsertEventTypeHandler, XtRemoveEventTypeHandler, XtRegisterExten-
       sionSelector, XtSetEventDispatcher, XtDispatchEventToWidget - extension
       event handling

SYNTAX
       void XtInsertEventTypeHandler(Widget widget, int	event_type, XtPointer
	      select_data, XtEventHandler proc,	XtPointer client_data, XtList-
	      Position position);

       void XtRemoveEventTypeHandler(Widget widget, int	event_type, XtPointer
	      select_data, XtEventHandler proc,	XtPointer client_data);

       void XtRegisterExtensionSelector(Display* display, int min_event_type,
	      int max_event_type, XtExtensionSelectProc	proc, XtPointer
	      client_data);

       XtEventDispatchProc XtSetEventDispatcher(Widget widget, int event_type,
	      XtEventDispatchProc proc);

       Boolean XtDispatchEventToWidget(Widget widget, XEvent* event);

ARGUMENTS
       widget	 Specifies the widget for this event handler.  Must be of
		 class Core or any subclass thereof.

       event_type
		 Specifies the event type.

       select_data
		 Specifies data	used to	select or deselect events from the
		 server.

       proc	 Specifies the proc.

       client_data
		 Specifies additional data to be passed	to the event handler.

       position	 Specifies when	the event handler is to	be called relative to
		 other previously registered handlers.

       display	 Specifies the display.

       min_event_type, max_event_type
		 Specifies the range of	event types for	this extension.

       event	 Specifies a pointer to	the event to be	dispatched.

DESCRIPTION
       The XtInsertEventTypeHandler function registers a procedure with	the
       dispatch	mechanism that is to be	called when an event that matches the
       specified event_type is dispatched to the specified widget.

       If event_type is	one of the core	X protocol events then select_data
       must be a pointer to a value of type EventMask, indicating the event
       mask to be used to select for the desired event.	 This event mask will
       be included in the value	returned by XtBuildEventMask.  If the widget
       is realized XtInsertEventTypeHandler calls XSelectInput if necessary.
       Specifying NULL for select_data is equivalent to	specifying a pointer
       to an event mask	containing 0. This is similar to the XtInsertRawEven-
       tHandler	function.

       If event_type specifies an extension event type then the	semantics of
       the data	pointed	to by select_data are defined by the extension selec-
       tor registered for the specified	event type.

       In either case the Intrinsics are not required to copy the data pointed
       to by select_data, so the caller	must ensure that it remains valid as
       long as the event handler remains registered with this value of se-
       lect_data.

       The position argument allows the	client to control the order of the in-
       vocation	of event handlers registered for the same event	type. If the
       client does not care about the order, it	should normally	specify
       XtListTail, which registers this	event handler after any	previously
       registered handlers for this event type.

       The XtRemoveEventTypeHandler function unregisters an even handler reg-
       istered with XtInsertEventTypeHandler for the specified event type. The
       request is ignored if client_data does not match	the value given	with
       the handler was registered.

       If event_type specifies on of the core X	protocol events, select_data
       must be a pointer to a value of type EventMask, indicating the mask to
       be used to deselect for the appropriate event.  If the widget is	real-
       ized, XtRemoveEventTypeHandler calls XSelectInput if necessary. Speci-
       fying NULL for select_data is equivalent	to specifying a	pointer	to an
       event mask containing 0.	This is	similar	to the XtRemoveRawEventHandler
       function.

       If event_type specifies an extension event type then the	semantics of
       the data	pointed	to by select_data are defined by the extension selec-
       tor registered for the specified	event type.

       The XtRegisterExtensionSelector function	registers a procedure to ar-
       range for the delivery of extension events to widgets.

       If min_event_type and max_event_type match the parameters to a previous
       call to XtRegisterExtensionSelector for the same	display, the proc and
       client_data replace the previously registered values. If	the range
       specified by min_event_type and max_event_type overlaps the range of
       the parameters to a previous call for the same display in any other
       way, an error results.

       The XtSetEventDispatcher	function registers the event dispatcher	proce-
       dure specified by proc for events with the type event_type. The previ-
       ously registered	dispatcher (or the default dispatcher if there was no
       previously registered dispatcher) is returned. If proc is NULL, the de-
       fault procedure is restored for the specified type.

       In the future, when XtDispatchEvent is called with an event of
       event_type, the specified proc (or the default dispatcher) will be in-
       voked to	determine a widget ot which to dispatch	the event.

       The XtDispatchEventToWidget function scans the list of registered event
       handlers	for the	specified widget and calls each	handler	that has been
       registered for the specified event type,	subject	to the con-
       tinue_to_dispatch value returned	by each	handler. The Intrinsics	behave
       as if event handlers were registered at the head	of the list for	Ex-
       pose, NoExpose, GraphicsExpose, and VisibilityNotify events to invoke
       the widget's expose procedure according to the exposure compression
       rules and to update the widget's	visible	field if visible_interest is
       True.  These internal event handlers never set continue_to_dispatch to
       False.

       XtDispatchEventToWidget returns True if any event handler was called
       and False otherwise.

SEE ALSO
       XtGetKeyboardFocusWidget(3)
       X Toolkit Intrinsics - C	Language Interface
       Xlib - C	Language X Interface

X Version 11			  libXt	1.1.5	   XtInsertEventTypeHandler(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | SEE ALSO

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