XSetInputFocus(3X11)RISC/os Reference Manual XSetInputFocus(3X11)



NAME
     XSetInputFocus, XGetInputFocus - control input focus

SYNTAX
     XSetInputFocus(display, focus, revert_to, time)
           Display *display;
           Window focus;
           int revert_to;
           Time time;

     XGetInputFocus(display, focus_return, revert_to_return)
           Display *display;
           Window *focus_return;
           int *revert_to_return;

ARGUMENTS
     display   Specifies the connection to the X server.

     focus     Specifies the window, PointerRoot, or None.

     focus_return
               Returns the focus window, PointerRoot, or None.

     revert_to Specifies where the input focus reverts to if the
               window becomes not viewable.  You can pass Revert-
               ToParent, RevertToPointerRoot, or RevertToNone.

     revert_to_return
               Returns the current focus state (RevertToParent,
               RevertToPointerRoot, or RevertToNone).

     time      Specifies the time.  You can pass either a times-
               tamp or CurrentTime.

DESCRIPTION
     The XSetInputFocus function changes the input focus and the
     last-focus-change time.  It has no effect if the specified
     time is earlier than the current last-focus-change time or
     is later than the current X server time.  Otherwise, the
     last-focus-change time is set to the specified time
     (CurrentTime is replaced by the current X server time).
     XSetInputFocus causes the X server to generate FocusIn and
     FocusOut events.

     Depending on the focus argument, the following occurs:

     ⊕    If focus is None, all keyboard events are discarded
          until a new focus window is set, and the revert_to
          argument is ignored.

     ⊕    If focus is a window, it becomes the keyboard's focus
          window.  If a generated keyboard event would normally



                         Printed 1/24/91         Release 4 Page 1

XSetInputFocus(3X11)RISC/os Reference Manual XSetInputFocus(3X11)



          be reported to this window or one of its inferiors, the
          event is reported as usual. Otherwise, the event is
          reported relative to the focus window.

     ⊕    If focus is PointerRoot, the focus window is dynami-
          cally taken to be the root window of whatever screen
          the pointer is on at each keyboard event. In this case,
          the revert_to argument is ignored.

     The specified focus window must be viewable at the time
     XSetInputFocus is called, or a BadMatch error results.  If
     the focus window later becomes not viewable, the X server
     evaluates the revert_to argument to determine the new focus
     window as follows:

     ⊕    If revert_to is RevertToParent, the focus reverts to
          the parent (or the closest viewable ancestor), and the
          new revert_to value is taken to be RevertToNone.

     ⊕    If revert_to is RevertToPointerRoot or RevertToNone,
          the focus reverts to PointerRoot or None, respectively.
          When the focus reverts, the X server generates FocusIn
          and FocusOut events, but the last-focus-change time is
          not affected.

     XSetInputFocus can generate BadMatch, BadValue, and BadWin-
     dow errors.

     The XGetInputFocus function returns the focus window and the
     current focus state.

DIAGNOSTICS
     BadValue  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 gen-
               erate this error.

     BadWindow A value for a Window argument does not name a
               defined Window.

SEE ALSO
     XWarpPointer(3X11)
     Xlib - C Language X Interface










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