CODEWITHSUNDEEP
androidgesturegesturesgesture-recognition
Violet Giraffe
Violet Giraffe

Reputation: 33589

How to combine ScaleGestureDetector.SimpleOnScaleGestureListener and GestureDetector.SimpleOnGestureListener properly?

My app needs to detect simple gestures (scroll, tap, long tap), and pinch zoom. Either detector works fine on its own - GestureDetector.SimpleOnGestureListener for tap / scroll and ScaleGestureDetector.SimpleOnScaleGestureListener for pinch zoom. The problem is combining the two. More specifically, it is very hard to start pinch zoom so that a couple of onScroll events are not generated before onScaleBegin.

Is there any good way to fix this? The only solution I can think about is buffer a few events before processing them (event queue), and discard onScroll / onTap without processing once onScaleBegin is detected. But that would introduce input lag (which my app already has and I don't want to make it even worse).

Upvotes: 1

Views: 2473

Answers (1)

pskink
pskink

Reputation: 24720

try this:

@Override
public boolean onTouchEvent(MotionEvent event) {
    boolean res = mScaleGestureDetector.onTouchEvent(event);
    if (!mScaleGestureDetector.isInProgress()) {
        res = mGestureDetector.onTouchEvent(event);
    }
    return res;
}

Upvotes: 3

Related Questions