SYNOPSIS¶
#include <X11/extensions/XInput.h>
int XGrabDeviceButton( Display *display,
XDevice *device,
unsigned int button,
unsigned int modifiers,
XDevice* modifier_device,
Window grab_window,
Bool owner_events,
unsigned int event_count,
XEventClass *event_list,
int this_device_mode,
int other_devices_mode);
int XUngrabDeviceButton( Display *display,
XDevice *device,
unsigned int button,
unsigned int modifiers,
XDevice* modifier_device,
Window grab_window);
display
Specifies the connection to the X server.
device
Specifies the device that is to be grabbed or released
button
Specifies the device button that is to be grabbed or
released or AnyButton.
modifiers
Specifies the set of keymasks or AnyModifier. The mask is
the bitwise inclusive OR of the valid keymask bits.
Valid bits are: ShiftMask, LockMask, ControlMask,
Mod1Mask, Mod2Mask, Mod3Mask, Mod4Mask, Mod5Mask.
modifier_device
specifies the device whose modifiers are to be used. If
the modifier_device specified is NULL, the X keyboard
will be used as the modifier_device.
grab_window
Specifies the grab window.
owner_events
Specifies a Boolean value that indicates whether the
device events are to be reported as usual or reported
with respect to the grab window if selected by the event
list.
event_count
Specifies the number of event classes in the event list.
event_list
Specifies which events are reported to the client.
this_device_mode
Specifies further processing of events from this
device. You can pass GrabModeSync or GrabModeAsync.
other_devices_mode
Specifies further processing of events from all other
devices. You can pass GrabModeSync or GrabModeAsync.
DESCRIPTION¶
The XGrabDeviceButton request establishes a passive grab. In
the future, the device is actively grabbed (as for XGrabDevice,
the last-grab time is set to the time at which the button was
pressed (as transmitted in the DeviceButtonPress event), and
the DeviceButtonPress event is reported if all of the following
conditions are true:
* The device is not grabbed, and the specified button is
logically pressed when the specified modifier keys are
logically down on the specified modifier device and no
other buttons or modifier keys are logically down.
* Either the grab window is an ancestor of (or is) the focus
window, OR the grab window is a descendent of the focus
window and contains the device.
* A passive grab on the same button/modifier combination does
not exist on any ancestor of grab_window.
The interpretation of the remaining arguments is as for
XGrabDevice. The active grab is terminated automatically when
the logical state of the device has all buttons released
(independent of the logical state of the 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/modifier 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.
A modifier_device of NULL indicates that the X keyboard is to
be used as the modifier_device.
If some other client has already issued a XGrabDeviceButton
with the same button/modifier 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. XGrabDeviceButton has no effect on an active grab.
XGrabDeviceButton can generate BadClass, BadDevice, BadMatch,
BadValue, and BadWindow errors.
The XUngrabDeviceButton request releases the passive grab for a
button/modifier combination on the specified window if it was
grabbed by this client. A modifier 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.
XUngrabDeviceButton has no effect on an active grab.
A modifier_device of NULL indicates that the X keyboard should
be used as the modifier_device.
XUngrabDeviceButton can generate BadDevice, BadMatch, BadValue
and BadWindow errors.
