XT FUNCTIONS XtAddEventHandler(3xt)
NAME
XtAddEventHandler, XtAddRawEventHandler, XtRemoveEvent-
Handler, XtRemoveRawEventHandler, XtInsertEventHandler,
XtInsertRawEventHandler - add and remove event handlers
SYNTAXcc [ flag... ] file... -lXt [ library... ]
void XtAddEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data);
void XtAddRawEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data);
void XtRemoveEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data);
void XtRemoveRawEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data);
void XtInsertEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data, XtListPosition position);
void XtInsertRawEventHandler(Widget w, EventMask event_mask,
Boolean nonmaskable, XtEventHandler proc, XtPointerclient_data, XtListPosition position);
typedef enum { XtListHead, XtListTail } XtListPosition; ARGUMENTSclient_data
Specifies additional data to be passed to the client's event handler.event_mask
Specifies the event mask for which to call or unregister this procedure. nonmaskable Specifies a Boolean value that indicates whether this procedure should be called or removed on the nonmaskable events (GraphicsExpose, NoExpose, SelectionClear, SelectionRequest, SelectionNotify, ClientMessage, and MappingNotify). proc Specifies the procedure that is to be added or removed. X Version 11 Last change: libXt 1.0.8 1 XT FUNCTIONS XtAddEventHandler(3xt) w Specifies the widget for which this event handler is being registered. position Specifies when the event handler is to be called relative to other previously registered handlers.DESCRIPTION
The XtAddEventHandler function registers a procedure with the dispatch mechanism that is to be called when an event that matches the mask occurs on the specified widget. If the procedure is already registered with the sameclient_data, the specified mask is ORed into the existing
mask. If the widget is realized, XtAddEventHandler calls XSelectInput, if necessary.The XtAddRawEventHandler function is similar to XtAddEvent-
Handler except that it does not affect the widget's mask and never causes an XSelectInput for its events. Note that the widget might already have those mask bits set because of other nonraw event handlers registered on it.The XtRemoveRawEventHandler function stops the specified
procedure from receiving the specified events. Because the procedure is a raw event handler, this does not affect the widget's mask and never causes a call on XSelectInput. XtInsertEventHandler is identical to XtAddEventHandler with the additional position argument. if position is XtListHead, the event handler is registered to that it will be called before any event handlers that were previously registered for the same widget. If position is XtListTail, the event handler is registered to be called after any previously registered event handlers. If the procedure is alreadyregistered with the same client_data value, the specified
mask augments the existing mask and the procedure is reposi-
tioned in the list. XtInsertRawEventHandler is similar to XtInsertEventHandler except that it does not modify the widget's event mask and never causes an XSelectInput for the specified events. If the procedure is already registered with the sameclient_data value, the specified mask augments the existing
mask and the procedure is repositioned in the list.SEE ALSO
XtAppNextEvent(3Xt), XtBuildEventMask(3Xt)X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface
ATTRIBUTES
See attributes(5) for descriptions of the following X Version 11 Last change: libXt 1.0.8 2 XT FUNCTIONS XtAddEventHandler(3xt) attributes:__________________________________________________________________
| 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