@Override
        public boolean onDoubleTap(MotionEvent e) {
            boolean consumed = false;
            if (doubleTapListener != null) {
                consumed = doubleTapListener.onDoubleTap(e);
            }
            if (state == State.NONE) {
                float targetZoom = (normalizedScale == minScale) ? maxScale : minScale;
                DoubleTapZoom doubleTap = new DoubleTapZoom(targetZoom, e.getX(), e.getY(), false);
                compatPostOnAnimation(doubleTap);
                consumed = true;
            }
            return consumed;
        }
Gesture Listener detects a single click or long click and passes that on
to the view's listener.

@author Ortiz
app/src/main/java/home/smart/fly/animations/customview/gallery/TouchImageView.java