title: Issue with updating view inside WindowManager in Android
body: <p>Here is the code for adding WindowManager to stay on top of other views.</p>
  
  <pre><code>private View mainView;
  private WindowManager.LayoutParams params;
  windowManager = (WindowManager) getSystemService(Service.WINDOW_SERVICE);
         params = new WindowManager.LayoutParams(
                 WindowManager.LayoutParams.WRAP_CONTENT,
                 WindowManager.LayoutParams.WRAP_CONTENT,
                 WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
                 WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_FULLSCREEN,
                 PixelFormat.TRANSLUCENT);
  
  params.gravity = Gravity.TOP | Gravity.LEFT;
  params.x = 0;
  params.y = 0;
  windowManager.addView(mainView, params);
  </code></pre>
  
  <p>It works fine. Inflating a layout inside the window manager and updating the layout dynamically. But I am unable to update the view. </p>
  
  <pre><code>LayoutInflater inflater = LayoutInflater.from(CallTimerService.this);
         mainView = inflater.inflate(R.layout.call_dialog, null);
  callerNameTv = (TextView) mainView.findViewById(R.id.caller_name);
  callerNameTv.setText(name);
  </code></pre>
  
  <p>setText method is called and there is no exception but the view is not updated. Can anyone point out the issue here?</p>