Swallowing Events
User callbacks must always return 0 unless they intend to swallow the event to which they are responding. To swallow the event, the callback should return 1.
Only user input, such as mouse click and keypress events, and commit events can be swallowed. If swallowed, no more callbacks are called for that event. If a user input event is swallowed, the user’s mouse click or keypress is ignored. If a commit event is swallowed, it is not placed into the GetUserEvent queue.
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Note The following events can be swallowed: EVENT_HSCROLL (Swallowable for tabs only.) EVENT_SELECTION_CHANGE (Swallowable for trees only.) |