XtAddEventHandler(3XtRISC/os Reference ManuXtAddEventHandler(3Xt)



NAME
     XtAddEventHandler, XtAddRawEventHandler, XtRemo-
     veEventHandler XtRemoveRawEventHandler - add and remove
     event handlers

SYNTAX
     void XtAddEventHandler(w, event_mask, nonmaskable, proc,
     client_data)
           Widget w;
           EventMask event_mask;
           Boolean nonmaskable;
           XtEventHandler proc;
           XtPointer client_data;

     void XtAddRawEventHandler(w, event_mask, nonmaskable, proc,
     client_data)
           Widget w;
           EventMask event_mask;
           Boolean nonmaskable;
           XtEventHandler proc;
           XtPointer client_data;

     void XtRemoveEventHandler(w, event_mask, nonmaskable, proc,
     client_data)
           Widget w;
           EventMask event_mask;
           Boolean nonmaskable;
           XtEventHandler proc;
           XtPointer client_data;

     void XtRemoveRawEventHandler(w, event_mask, nonmaskable,
     proc, client_data)
           Widget w;
           EventMask event_mask;
           Boolean nonmaskable;
           XtEventHandler proc;
           XtPointer client_data;

ARGUMENTS
     client_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,



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XtAddEventHandler(3XtRISC/os Reference ManuXtAddEventHandler(3Xt)



               ClientMessage, and MappingNotify).

     proc      Specifies the procedure that is to be added or
               removed.

     w         Specifies the widget for which this event handler
               is being registered.

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 same
     client_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 XtAd-
     dEventHandler 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 XtAddRawEventHandler function is similar to XtAd-
     dEventHandler 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.

SEE ALSO
     XtAppNextEvent(3Xt), XtBuildEventMask(3Xt)
     X Toolkit Intrinsics - C Language Interface
     Xlib - C Language X Interface

















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