xtremoveraweventhandler(1) [hpux man page]
XtRemoveRawEventHandler() XtRemoveRawEventHandler()
Name
XtRemoveRawEventHandler - remove a raw event handler, or change the conditions under which it is called.
Synopsis
void XtRemoveRawEventHandler(w, event_mask, nonmaskable, proc, client_data)
Widget w;
EventMask event_mask;
Boolean nonmaskable;
XtEventHandler proc;
XtPointer client_data;
Inputs
w Specifies the widget for which this handler is registered. Must be of class Core or any subclass thereof.
event_mask
Specifies the events for which to unregister this handler.
nonmaskable
Specifies whether this handler should be unregistered for nonmaskable events.
proc Specifies the handler procedure.
client_data
Specifies the client data with which the procedure was registered.
Description
XtRemoveRawEventHandler() stops the proc/client_data event handler pair registered with XtAddRawEventHandler() or XtInsertRawEventHandler()
from being called from widget w in response to the events specified in event_mask. In addition, if nonmaskable is True, then the handler
will no longer be called in response to the nonmaskable events: GraphicsExpose, NoExpose, SelectionClear, SelectionRequest, SelectionNo-
tify, ClientMessage, and MappingNotify.
A handler is removed only if both the procedure proc and client_data match a previously registered handler/data pair. If a handler to be
removed fails to match a procedure, or if it has been registered with a different value of client_data, XtRemoveRawEventHandler() returns
without reporting an error.
XtRemoveRawEventHandler() accepts the special value XtAllEvents in the event_handler argument as a signal that the event handler should no
longer be called in response to any maskable events. This value should not be combined with other event mask bits, and should not be used
to select events in other functions.
Because the procedure is a raw event handler, this function does not affect the widget's event mask and never calls XSelectInput().
Usage
Note that XtRemoveRawEventHandler() does not necessarily remove an event handler; rather, it modifies the conditions for which it is
called. To prevent an event handler from being called at all, call XtRemoveRawEventHandler() with an event_mask of XtAllEvents and with
nonmaskable True.
To remove or change the event mask for a event handler registered with XtAddEventHandler() or XtInsertEventHandler(), use XtRemoveEven-
tHandler().
Structures
Each of the event types listed in the table below set a single bit in an event mask. The event_mask argument is formed by combining these
symbols with the bitwise OR operator ( ). Note that the nonmaskable event types do not appear in this table and cannot be requested in an
event mask.
NoEventMask Button1MotionMask StructureNotifyMask
KeyPressMask Button2MotionMask ResizeRedirectMask
KeyReleaseMask Button3MotionMask SubstructureNotifyMask
ButtonPressMask Button4MotionMask SubstructureRedirectMask
ButtonReleaseMask Button5MotionMask FocusChangeMask
EnterWindowMask ButtonMotionMask PropertyChangeMask
LeaveWindowMask KeymapStateMask ColormapChangeMask
PointerMotionMask ExposureMask OwnerGrabButtonMask
PointerMotionHintMask VisibilityChangeMask
See Appendix C, Event Reference, for more information on event types and masks.
In addition to these standard X event masks, the Intrinsics define a special value for use by this function:
/* XtAllEvents is valid only for XtRemoveEventHandler and
* XtRemoveRawEventHandler; don't use it to select events!
*/
#define XtAllEvents ((EventMask) -1L)
See Also
XtAddRawEventHandler(1), XtInsertRawEventHandler(1), XtRemoveEventHandler(1),
XtEventHandler(2).
Xt - Event Handling XtRemoveRawEventHandler()
Check Out this Related Man Page
XtAddEventHandler() XtAddEventHandler() Name XtAddEventHandler - register a procedure to be called when specified events occur on a widget. Synopsis void XtAddEventHandler(w, event_mask, nonmaskable, proc, client_data) Widget w; EventMask event_mask; Boolean nonmaskable; XtEventHandler proc; XtPointer client_data; Inputs w Specifies the widget for which this event handler is being registered. Must be of class Core or any subclass thereof. event_mask Specifies the event type that will trigger the handler. nonmaskable Specifies whether this procedure should be called on nonmaskable event types. proc Specifies the handler procedure. client_data Specifies additional data to be passed to the event handler. Description XtAddEventHandler() registers the procedure proc and the data client_data with the Intrinsics event dispatching mechanism. When an event of one of the types set in event_mask occurs on the window of the widget w, proc will be invoked and client_data passed as one of its argu- ments. If the window of the widget is not already receiving events of the specified types, XtAddEventHandler() calls XSelectInput() to ensure that they will be delivered. Additionally, if the handler is registered with the nonmaskable argument True, then it will also be invoked when any of the nonmaskable event types occur. These events are GraphicsExpose, NoExpose, SelectionClear, SelectionRequest, Selec- tionNotify, ClientMessage, and MappingNotify. Ordinarily, nonmaskable events are of interest only to the Intrinsics. If the specified procedure/data pair has already been registered for this widget, then the event_mask argument augments the event mask already registered for the handler, and the procedure will only be called once for any particular event. The same procedure may be regis- tered multiple times with different values of client_data, and each instance will be treated as a separate handler. See XtEventHandler(2) for an explanation of how to write an event handler procedure. Usage Neither applications nor widgets often need to use event handlers. Using action procedures and translation tables provides a more flexible way to respond to input events. The Intrinsics do not specify the order in which event handlers will be called when an event arrives. As of Release 4, however, the func- tion XtInsertEventHandler() will register an event handler that will be called before or after all previously registered handlers. An event handler can be removed with XtRemoveEventHandler(). Structures Each of the event mask symbols listed in the table below set a single bit in an event mask. The event_mask argument is formed by combining these symbols with the bitwise OR operator ( ). Note that the nonmaskable event types do not appear in this table and cannot be requested in an event mask. NoEventMask Button1MotionMask StructureNotifyMask KeyPressMask Button2MotionMask ResizeRedirectMask KeyReleaseMask Button3MotionMask SubstructureNotifyMask ButtonPressMask Button4MotionMask SubstructureRedirectMask ButtonReleaseMask Button5MotionMask FocusChangeMask EnterWindowMask ButtonMotionMask PropertyChangeMask LeaveWindowMask KeymapStateMask ColormapChangeMask PointerMotionMask ExposureMask OwnerGrabButtonMask PointerMotionHintMask VisibilityChangeMask See Appendix C, Event Reference, for more information on event types and masks. See Also XtAddRawEventHandler(1), XtInsertEventHandler(1), XtRemoveEventHandler(1), XtEventHandler(2). Xt - Event Handling XtAddEventHandler()