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XGrabButton, XUngrabButton
- grab pointer buttons
- int XGrabButton(Display *display, unsigned
int button,
- unsigned int modifiers, Window grab_window, Bool owner_events,
unsigned int event_mask, int pointer_mode, keyboard_mode, Window confine_to,
Cursor cursor);
- int XUngrabButton(Display *display, unsigned int button,
- unsigned int modifiers, Window grab_window);
- button
- Specifies
the pointer button that is to be grabbed or released or AnyButton.
- confine_to
- Specifies
the window to confine the pointer in or None.
- cursor
- Specifies the cursor
that is to be displayed or None.
- display
- Specifies the connection to the
X server.
- event_mask
- Specifies which pointer events are reported to the client.
The mask is the bitwise inclusive OR of the valid pointer event mask bits.
- grab_window
- Specifies the grab window.
- keyboard_mode
- Specifies further processing
of keyboard events. You can pass GrabModeSync or GrabModeAsync.
- modifiers
- Specifies
the set of keymasks or AnyModifier. The mask is the bitwise inclusive
OR of the valid keymask bits.
- owner_events
- Specifies a Boolean value that
indicates whether the pointer events are to be reported as usual or reported
with respect to the grab window if selected by the event mask.
- pointer_mode
- Specifies
further processing of pointer events. You can pass GrabModeSync or GrabModeAsync.
The XGrabButton function establishes a passive grab. In the
future, the pointer is actively grabbed (as for XGrabPointer), the last-pointer-grab
time is set to the time at which the button was pressed (as transmitted
in the ButtonPress event), and the ButtonPress event is reported if
all of the following conditions are true:
- The pointer is not grabbed, and
the specified button is logically pressed when the specified modifier keys
are logically down, and no other buttons or modifier keys are logically
down.
- The grab_window contains the pointer.
- The confine_to window (if any)
is viewable.
- A passive grab on the same button/key combination does not
exist on any ancestor of grab_window.
The interpretation of the remaining
arguments is as for XGrabPointer. The active grab is terminated automatically
when the logical state of the pointer has all buttons released (independent
of the state of the logical modifier keys).
Note that the logical state
of a device (as seen by client applications) may lag the physical state
if device event processing is frozen.
This request overrides all previous
grabs by the same client on the same button/key combinations on the same
window. A modifiers of AnyModifier is equivalent to issuing the grab
request for all possible modifier combinations (including the combination
of no modifiers). It is not required that all modifiers specified have
currently assigned KeyCodes. A button of AnyButton is equivalent to
issuing the request for all possible buttons. Otherwise, it is not required
that the specified button currently be assigned to a physical button.
If
some other client has already issued a XGrabButton with the same button/key
combination on the same window, a BadAccess error results. When using
AnyModifier or AnyButton, the request fails completely, and a BadAccess
error results (no grabs are established) if there is a conflicting grab
for any combination. XGrabButton has no effect on an active grab.
XGrabButton
can generate BadCursor, BadValue, and BadWindow errors.
The XUngrabButton
function releases the passive button/key combination on the specified
window if it was grabbed by this client. A modifiers of AnyModifier is
equivalent to issuing the ungrab request for all possible modifier combinations,
including the combination of no modifiers. A button of AnyButton is
equivalent to issuing the request for all possible buttons. XUngrabButton
has no effect on an active grab.
XUngrabButton can generate BadValue
and BadWindow errors.
- BadCursor
- A value for a Cursor argument
does not name a defined Cursor.
- 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 generate
this error.
- BadWindow
- A value for a Window argument does not name a defined
Window.
XAllowEvents(3X11)
, XGrabPointer(3X11)
, XGrabKey(3X11)
,
XGrabKeyboard(3X11)
,
Xlib - C Language X Interface
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