1Tk_CreateClientMessageHandler(T3k)Library ProceduTrke_sCreateClientMessageHandler(3)
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8 Tk_CreateClientMessageHandler, Tk_DeleteClientMessageHandler - asso‐
9 ciate procedure callback with ClientMessage type X events
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12 #include <tk.h>
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14 Tk_CreateClientMessageHandler(proc)
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16 Tk_DeleteClientMessageHandler(proc)
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19 Tk_ClientMessageProc *proc (in) Procedure to invoke whenever
20 a ClientMessage X event
21 occurs on any display.
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26 Tk_CreateClientMessageHandler arranges for proc to be invoked in the
27 future whenever a ClientMessage X event occurs that is not handled by
28 WM_PROTOCOL. Tk_CreateClientMessageHandler is intended for use by
29 applications which need to watch X ClientMessage events, such as drag
30 and drop applications.
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32 The callback to proc will be made by Tk_HandleEvent; this mechanism
33 only works in programs that dispatch events through Tk_HandleEvent (or
34 through other Tk procedures that call Tk_HandleEvent, such as
35 Tk_DoOneEvent or Tk_MainLoop).
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37 Proc should have arguments and result that match the type Tk_ClientMes‐
38 sageProc:
39 typedef int Tk_ClientMessageProc(
40 Tk_Window tkwin,
41 XEvent *eventPtr);
42 The tkwin parameter to proc is the Tk window which is associated with
43 this event. EventPtr is a pointer to the X event.
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45 Whenever an X ClientMessage event is processed by Tk_HandleEvent, the
46 proc is called if it was not handled as a WM_PROTOCOL. The return
47 value from proc is normally 0. A non-zero return value indicates that
48 the event is not to be handled further; that is, proc has done all pro‐
49 cessing that is to be allowed for the event.
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51 If there are multiple ClientMessage event handlers, each one is called
52 for each event, in the order in which they were established.
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54 Tk_DeleteClientMessageHandler may be called to delete a previously-cre‐
55 ated ClientMessage event handler: it deletes each handler it finds that
56 matches the proc argument. If no such handler exists, then Tk_Delete‐
57 ClientMessageHandler returns without doing anything. Although Tk sup‐
58 ports it, it's probably a bad idea to have more than one callback with
59 the same proc argument.
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63 bind, callback, event, handler
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67Tk 8.4 Tk_CreateClientMessageHandler(3)