code: private void removeMsg(final AppMsg appMsg) {
          clearMsg(appMsg);
          final View view = appMsg.getView();
          ViewGroup parent = ((ViewGroup) view.getParent());
          if (parent != null) {
              appMsg.mOutAnimation.setAnimationListener(new OutAnimationListener(appMsg));
              view.clearAnimation();
              view.startAnimation(appMsg.mOutAnimation);
          }
  
          Message msg = obtainMessage(MESSAGE_DISPLAY);
          sendMessage(msg);
      }
docs: Removes the {@link AppMsg}'s view after it's display duration.
  
  @param appMsg The {@link AppMsg} added to a {@link ViewGroup} and should be removed.s