Sets the state of @sequence in @gesture. Sequences start
in state #GTK_EVENT_SEQUENCE_NONE, and whenever they change
state, they can never go back to that state. Likewise,
sequences in state #GTK_EVENT_SEQUENCE_DENIED cannot turn
back to a not denied state. With these rules, the lifetime
of an event sequence is constrained to the next four:
Note: Due to event handling ordering, it may be unsafe to
set the state on another gesture within a #GtkGesture::begin
signal handler, as the callback might be executed before
the other gesture knows about the sequence. A safe way to
perform this could be:
If both gestures are in the same group, just set the state on
the gesture emitting the event, the sequence will be already
be initialized to the group's global state when the second
gesture processes the event.
Sets the state of @sequence in @gesture. Sequences start in state #GTK_EVENT_SEQUENCE_NONE, and whenever they change state, they can never go back to that state. Likewise, sequences in state #GTK_EVENT_SEQUENCE_DENIED cannot turn back to a not denied state. With these rules, the lifetime of an event sequence is constrained to the next four:
* None * None → Denied * None → Claimed * None → Claimed → Denied
Note: Due to event handling ordering, it may be unsafe to set the state on another gesture within a #GtkGesture::begin signal handler, as the callback might be executed before the other gesture knows about the sequence. A safe way to perform this could be:
|[ static void first_gesture_begin_cb (GtkGesture *first_gesture, GdkEventSequence *sequence, gpointer user_data) { gtk_gesture_set_sequence_state (first_gesture, sequence, GTK_EVENT_SEQUENCE_CLAIMED); gtk_gesture_set_sequence_state (second_gesture, sequence, GTK_EVENT_SEQUENCE_DENIED); }
static void second_gesture_begin_cb (GtkGesture *second_gesture, GdkEventSequence *sequence, gpointer user_data) { if (gtk_gesture_get_sequence_state (first_gesture, sequence) == GTK_EVENT_SEQUENCE_CLAIMED) gtk_gesture_set_sequence_state (second_gesture, sequence, GTK_EVENT_SEQUENCE_DENIED); } ]|
If both gestures are in the same group, just set the state on the gesture emitting the event, the sequence will be already be initialized to the group's global state when the second gesture processes the event.