code: @Override
      public void doAction(Action action) {
          BaseComponent parent = getParent();
          
          switch (action) {
              case REMOVE:
                  ActionListener.unbindActionListeners(this, actionListeners);
                  detach();
                  break;
              
              case HIDE:
              case COLLAPSE:
                  setVisible(false);
                  break;
              
              case SHOW:
              case EXPAND:
                  setVisible(true);
                  break;
              
              case TOP:
                  parent.addChild(this, 0);
                  break;
          }
          
          if (parent != null) {
              EventUtil.post(MainController.ALERT_ACTION_EVENT, parent, action);
          }
      }
docs: Perform the specified action on the drop container. Also, notifies the container's parent
  that an action has occurred.
  
  @param action An action.