XIAllowEvents - Man Page
Release queued events
Synopsis
#include <X11/extensions/XInput2.h>
Status XIAllowEvents( Display *display, int deviceid, int event_mode, Time time );
Status XIAllowTouchEvents( Display *dpy, int deviceid, unsigned int touchid, Window grab_window, int event_mode );
display Specifies the connection to the X server.
device Specifies the device that is to be grabbed or released
event_mode Specifies whether a device is to be thawed and events are to be replayed, or how to handle a grabbed touch sequence.
time A valid server time or CurrentTime.
touchid The ID of the touch sequence to accept or reject. The value is ignored for event modes other than AcceptTouch and RejectTouch.
grab_window The window on which to accept or reject a touch sequence grab. The value is ignored for event modes other than AcceptTouch and RejectTouch.
Description
The XIAllowEvents request releases some queued events if the client has caused a device to freeze. It also is used to handle touch grab and ownership processing.
The function has no effect if the specified time is earlier than the last-grab time of the most recent active grab for the client, or if the specified time is later than the current X server time. The time parameter must be CurrentTime for requests with event modes of XIAcceptTouch and XIRejectTouch.
The following describes the processing that occurs depending on what constant you pass to the event_mode argument:
XIAsyncDevice: If the specified device is frozen by the client, event processing for that device continues as usual. If the device is frozen multiple times by the client on behalf of multiple separate grabs, XIAsyncDevice thaws for all. XIAsyncDevice has no effect if the specified device is not frozen by the client, but the device need not be grabbed by the client.
XISyncDevice: If the specified device is frozen and actively grabbed by the client, event processing for that device continues normally until the next button press or release, or key press or release, or a gesture begin or end event (depending on the grab) is reported to the client. At this time, the specified device again appears to freeze. However, if the reported event causes the grab to be released, the specified device does not freeze. XISyncDevice has no effect if the specified device is not frozen by the client or is not grabbed by the client.
XIReplayDevice: If the specified device is actively grabbed by the client and is frozen as the result of an event having been sent to the client (either from the activation of a XIGrabButton or from a previous XIAllowEvents with mode SyncDevice, but not from a Grab), the grab is released and that event is completely reprocessed. This time, however, the request ignores any passive grabs at or above (towards the root) the grab window of the grab just released. The request has no effect if the specified device is not grabbed by the client or if it is not frozen as the result of an event. In case of gesture begin event being replayed, the original grabbing client will receive a XI_GesturePinchEnd or XI_GestureSwipeEnd event.
XIAsyncPairedDevice: If the paired master device is frozen by the client, event processing for it continues as usual. If the paired device is frozen multiple times by the client on behalf of multiple separate grabs, XIAsyncPairedDevice thaws for all. XIAsyncPairedDevice has no effect if the device is not frozen by the client, but those devices need not be grabbed by the client. XIAsyncPairedDevice has no effect if deviceid specifies a slave device.
XISyncPair: If both the device and the paired master device are frozen by the client, event processing (for both devices) continues normally until the next XI_ButtonPress, XI_ButtonRelease, XI_KeyPress, or XI_KeyRelease event is reported to the client for a grabbed device (button event for a pointer, key event for a 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 still grabbed, then a subsequent event for it will still cause both devices to freeze). XISyncPair has no effect unless both the device and the paired master device are frozen by the client. If the device or paired master device is frozen twice by the client on behalf of two separate grabs, XISyncPair thaws for both (but a subsequent freeze for XISyncPair will only freeze each device once). XISyncPair has no effect if deviceid specifies a slave device.
XIAsyncPair: If the device and the paired master device are frozen by the client, event processing for both devices continues normally. If a device is frozen twice by the client on behalf of two separate grabs, AsyncBoth thaws for both. XIAsyncPair has no effect unless both the device and the paired master device frozen by the client. XIAsyncPair has no effect if deviceid specifies a slave device.
XIAcceptTouch: The client is deemed to have taken control of the touch sequence once it owns the sequence. TouchEnd events will be sent to all clients listening to the touch sequence that have either grabbed the touch sequence on a child window of the grab_window or have received events for the touch sequence through event selection. These clients will no longer receive any TouchUpdate events.
XIRejectTouch: The client is no longer interested in the touch sequence, and will receive a XI_TouchEnd event. If the client is the current owner of the sequence, ownership will be passed on to the next listener.
Diagnostics
BadDevice An invalid deviceid was specified.
BadAccess This error may occur if event_mode is XIAcceptTouch and this client is not the current or potential owner of the specified touch ID.
BadValue This error may occur if event_mode is XIAcceptTouch and touch ID is invalid.
BadWindow A value for a grab_window argument does not name a defined Window.
See Also
XIGrabButton(3)
Referenced By
XIGrabButton(3), XIGrabDevice(3), XIGrabEnter(3).
09/05/2024