Connect to Begin signal.
Connect to Cancel signal.
Connect to End signal.
Connect to SequenceStateChanged signal.
Connect to Update signal.
If there are touch sequences being currently handled by gesture, returns true and fills in rect with the bounding box containing all active touches.
If there are touch sequences being currently handled by gesture, returns true and fills in x and y with the center of the bounding box containing all active touches.
Returns the logical gdk.device.Device that is currently operating on gesture.
Returns all gestures in the group of gesture
Returns the last event that was processed for sequence.
Returns the gdk.event_sequence.EventSequence that was last updated on gesture.
If sequence is currently being interpreted by gesture, returns true and fills in x and y with the last coordinates stored for that event sequence.
Returns the sequence state, as seen by gesture.
Returns the list of GdkEventSequences currently being interpreted by gesture.
Adds gesture to the same group than group_gesture.
Returns true if gesture is currently handling events corresponding to sequence.
Returns true if the gesture is currently active.
Returns true if both gestures pertain to the same group.
Returns true if the gesture is currently recognized.
Sets the state of sequence in gesture.
Sets the state of all sequences that gesture is currently interacting with.
Separates gesture into an isolated group.
Returns the event that is currently being handled by the controller.
Returns the device of the event that is currently being handled by the controller.
Returns the modifier state of the event that is currently being handled by the controller.
Returns the timestamp of the event that is currently being handled by the controller.
Gets the name of controller.
Gets the propagation limit of the event controller.
Gets the propagation phase at which controller handles events.
Returns the gtk.widget.Widget this controller relates to.
Resets the controller to a clean state.
Sets a name on the controller that can be used for debugging.
Sets the event propagation limit on the event controller.
Sets the propagation phase at which a controller handles events.
Sets a name on the controller that can be used for debugging.
gtk.gesture.Gesture is the base class for gesture recognition.
Although gtk.gesture.Gesture is quite generalized to serve as a base for multi-touch gestures, it is suitable to implement single-touch and pointer-based gestures (using the special null gdk.event_sequence.EventSequence value for these).
The number of touches that a gtk.gesture.Gesture need to be recognized is controlled by the property@Gtk.Gesture:n-points property, if a gesture is keeping track of less or more than that number of sequences, it won't check whether the gesture is recognized.
As soon as the gesture has the expected number of touches, it will check regularly if it is recognized, the criteria to consider a gesture as "recognized" is left to gtk.gesture.Gesture subclasses.
A recognized gesture will then emit the following signals:
Event propagation
In order to receive events, a gesture needs to set a propagation phase through gtk.event_controller.EventController.setPropagationPhase.
In the capture phase, events are propagated from the toplevel down to the target widget, and gestures that are attached to containers above the widget get a chance to interact with the event before it reaches the target.
In the bubble phase, events are propagated up from the target widget to the toplevel, and gestures that are attached to containers above the widget get a chance to interact with events that have not been handled yet.
States of a sequence
Whenever input interaction happens, a single event may trigger a cascade of gtk.gesture.Gestures, both across the parents of the widget receiving the event and in parallel within an individual widget. It is a responsibility of the widgets using those gestures to set the state of touch sequences accordingly in order to enable cooperation of gestures around the gdk.event_sequence.EventSequences triggering those.
Within a widget, gestures can be grouped through gtk.gesture.Gesture.group. Grouped gestures synchronize the state of sequences, so calling gtk.gesture.Gesture.setState on one will effectively propagate the state throughout the group.
By default, all sequences start out in the gtk.types.EventSequenceState.None state, sequences in this state trigger the gesture event handler, but event propagation will continue unstopped by gestures.
If a sequence enters into the gtk.types.EventSequenceState.Denied state, the gesture group will effectively ignore the sequence, letting events go unstopped through the gesture, but the "slot" will still remain occupied while the touch is active.
If a sequence enters in the gtk.types.EventSequenceState.Claimed state, the gesture group will grab all interaction on the sequence, by:
Note: if a sequence is set early to gtk.types.EventSequenceState.Claimed on gdk.types.EventType.TouchBegin/gdk.types.EventType.ButtonPress (so those events are captured before reaching the event widget, this implies gtk.types.PropagationPhase.Capture), one similar event will be emulated if the sequence changes to gtk.types.EventSequenceState.Denied. This way event coherence is preserved before event propagation is unstopped again.
Sequence states can't be changed freely. See gtk.gesture.Gesture.setState to know about the possible lifetimes of a gdk.event_sequence.EventSequence.
Touchpad gestures
On the platforms that support it, gtk.gesture.Gesture will handle transparently touchpad gesture events. The only precautions users of gtk.gesture.Gesture should do to enable this support are: