/** After creating view, Callback to notify activity bind Play service. */
 @Override
 public void onStart() {
   super.onStart();
   L.l("fragment", "onViewCreated");
   mActivity.allowBindService();
 }
 /** When stop, callback notify activity to unbind PlayService */
 @Override
 public void onStop() {
   super.onStop();
   L.l("fragment", "onDestroyView");
   mActivity.allowUnbindService();
 }