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<HTML><HEAD><TITLE>Xlib Programming Manual: XAllowEvents</TITLE></HEAD><BODY><H1 ALIGN=center>XAllowEvents</H1><H2>Syntax</H2><!.IN "XAllowEvents" "" "@DEF@"><CODE><PRE>XAllowEvents(<B>display</B>, <B>event_mode</B>, <B>time</B>) <A HREF="../display/opening.html#Display">Display</A> *<B>display</B>; int <B>event_mode</B>; <A HREF="pointer-grabbing.html#Time">Time</A> <B>time</B>; </PRE></CODE><H2>Arguments</H2><TABLE><TR><TD> <B>display</B><TD> Specifies the connection to the X server.<TR><TD> <B>event_mode</B><TD> Specifies the event mode.You can pass <B>AsyncPointer</B>, <B>SyncPointer</B>, <B>AsyncKeyboard</B>, <B>SyncKeyboard</B>,<B>ReplayPointer</B>, <B>ReplayKeyboard</B>,<B>AsyncBoth</B>,or<B>SyncBoth</B>.<TR><TD> <B>time</B><TD> Specifies the time.You can pass either a timestamp or<B>CurrentTime</B>.</TABLE><H2>Description</H2>The<B>XAllowEvents()</B>function releases some queued events if the client has caused a device to freeze.It has no effect if the specified time is earlier than the last-grabtime of the most recent active grab for the client or if the specified timeis later than the current X server time.Depending on the event_mode argument, the following occurs:<TABLE><TR><TD VALIGN=top><B>AsyncPointer<TD>If the pointer is frozen by the client,pointer event processing continues as usual.If the pointer is frozen twice by the client on behalf of two separate grabs,<B>AsyncPointer</B> thaws for both.<B>AsyncPointer</B>has no effect if the pointer is not frozen by the client,but the pointer need not be grabbed by the client.<TR><TD VALIGN=top><B>SyncPointer <TD>If the pointer is frozen and actively grabbed by the client,pointer event processing continues as usual until the next <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">ButtonPress</A></B> or <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">ButtonRelease</A></B> event is reported to the client.At this time, the pointer again appears to freeze.However, if the reported event causes the pointer grab to be released,the pointer does not freeze.<B>SyncPointer</B> has no effect if the pointer is not frozen by the clientor if the pointer is not grabbed by the client.<TR><TD VALIGN=top><B>ReplayPointer<TD>If the pointer is actively grabbed by the client and is frozen as the result ofan event having been sent to the client (either from the activation of a <B><A HREF="XGrabButton.html">XGrabButton()</A></B>or from a previous <B>XAllowEvents()</B>with mode <B>SyncPointer</B>but not from a <B><A HREF="XGrabPointer.html">XGrabPointer()</A></B>),the pointer grab is released and that event is completely reprocessed.This time, however, the function ignores any passive grabs at or above (towards the root of) the grab_window of the grab just released.The request has no effect if the pointer is not grabbed by the clientor if the pointer is not frozen as the result of an event.<TR><TD VALIGN=top><B>AsyncKeyboard <TD>If the keyboard is frozen by the client,keyboard event processing continues as usual.If the keyboard is frozen twice by the client on behalf of two separate grabs,<B>AsyncKeyboard</B> thaws for both.<B>AsyncKeyboard</B> has no effect if the keyboard is not frozen by the client,but the keyboard need not be grabbed by the client.<TR><TD VALIGN=top><B>SyncKeyboard<TD>If the keyboard is frozen and actively grabbed by the client,keyboard event processing continues as usual until the next <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">KeyPress</A></B> or <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">KeyRelease</A></B> event is reported to the client.At this time,the keyboard again appears to freeze.However, if the reported event causes the keyboard grab to be released,the keyboard does not freeze.<B>SyncKeyboard</B> has no effect if the keyboard is not frozen by the clientor if the keyboard is not grabbed by the client.<TR><TD VALIGN=top><B>ReplayKeyboard<TD>If the keyboard is actively grabbed by the client and is frozen as the result of an event having been sent to the client (either from theactivation of a <B><A HREF="XGrabKey.html">XGrabKey()</A></B>or from a previous <B>XAllowEvents()</B>with mode <B>SyncKeyboard</B> but not from a <B><A HREF="XGrabKeyboard.html">XGrabKeyboard()</A></B>),the keyboard grab is released and that event is completely reprocessed.This time, however, the function ignores any passive grabs at or above (towards the root of)the grab_window of the grab just released.The request has no effect if the keyboard is not grabbed by the clientor if the keyboard is not frozen as the result of an event.<TR><TD VALIGN=top><B>SyncBoth<TD>If both pointer and keyboard are frozen by the client,event processing for both devices continues as usual until the next<B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">ButtonPress</A></B>, <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">ButtonRelease</A></B>,<B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">KeyPress</A></B>, or <B><A HREF="../events/keyboard-pointer/keyboard-pointer.html">KeyRelease</A></B> event is reported to the client for a grabbed device (button event for the pointer, key event for the keyboard), at which time the devices again appear to freeze. However, if the reported event causes the grab to be released,then the devices do not freeze (but if the other device is stillgrabbed, then a subsequent event for it will still cause both devicesto freeze). <B>SyncBoth</B>has no effect unless both pointer and keyboardare frozen by the client.If the pointer or keyboard is frozen twiceby the client on behalf of two separate grabs, <B>SyncBoth</B> thaws for both (but a subsequent freeze for <B>SyncBoth</B> will only freeze each device once).<TR><TD VALIGN=top><B>AsyncBoth<TD>If the pointer and the keyboard are frozen by theclient, event processing for both devices continues as usual.If a device is frozen twice by the client on behalf of two separate grabs,<B>AsyncBoth</B> thaws for both.<B>AsyncBoth</B> has no effect unless bothpointer and keyboard are frozen by the client.</TABLE><P><B>AsyncPointer</B>, <B>SyncPointer</B>, and <B>ReplayPointer</B> have no effect on theprocessing of keyboard events.<B>AsyncKeyboard</B>, <B>SyncKeyboard</B>, and <B>ReplayKeyboard</B> have no effect on theprocessing of pointer events.It is possible for both a pointer grab and a keyboard grab (by the same or different clients) to be active simultaneously.If a device is frozen on behalf of either grab,no event processing is performed for the device.It is possible for a single device to be frozen because of both grabs.In this case,the freeze must be released on behalf of both grabs before events can again be processed.If a device is frozen twice by a single client,then a single<B>AllowEvents</B>releases both.<P><B>XAllowEvents()</B>can generate a<B>BadValue</B> error.<H2>Diagnostics</H2><TABLE><TR><TD><B>BadValue</B><TD> Some numeric value falls outside the range of values accepted by the request. Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error.</TABLE><H2>See also</H2>"<A HREF="resuming-event-processing.html">Resuming Event Processing</A>".<HR><ADDRESS><A HREF="http://tronche.com/">Christophe Tronche</A>, <A HREF="mailto:ch.tronche@computer.org">ch.tronche@computer.org</A></ADDRESS></BODY></HTML>⌨️ 快捷键说明
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