title: What is the purpose of GestureDetector.OnGestureListener versus GestureDetector.SimpleOnGestureListener?
body: <p>If GestureDetector.SimpleOnGestureListener does the same thing as GestureDetector.OnGestureListener but without requiring unused code, then what is the point of OnGestureListener at all? </p>
  
  <p>Rarely do I ever need to handle every type of gesture, and if I did need to do so I could do it in SimpleOnGestureListener anyways.</p>