onTouchEvent executes twice
It executes for every event. In this case it would be for the ACTION_DOWN and ACTION_UP event. It will also execute for the ACTION_MOVE event many, many times.
To have it only execute in one event, do something like this:
switch(event.getAction()){ case MotionEvent.ACTION_DOWN: ** CODE ** break; case MotionEvent.ACTION_MOVE: ** CODE ** break; case MotionEvent.ACTION_UP: ** CODE ** break;}