title: why can use getParent ().RequestDisallowInterceptTouchEvent (true) disallow Intercepted
body: <pre><code>@Override   
  public boolean dispatchTouchEvent(MotionEvent ev) {  
      // why this code can be executed.
      getParent().requestDisallowInterceptTouchEvent(true); 
      return super.dispatchTouchEvent(ev);   
  } 
  </code></pre>
  
  <p><code>getParent().requestDisallowInterceptTouchEvent(true)</code> tell parent don't intercept touch event. but if parent already intercept touch event, the event can't pass to <strong>child view</strong>, and child view how to execute <code>getParent().requestDisallowInterceptTouchEvent(true)</code> ?</p>