code: function () {
              Panel.superclass.initEvents.call(this);
  
              var SIGNATURE = CustomEvent.LIST;
  
              /**
              * CustomEvent fired after the modality mask is shown
              * @event showMaskEvent
              */
              this.showMaskEvent = this.createEvent(EVENT_TYPES.SHOW_MASK);
              this.showMaskEvent.signature = SIGNATURE;
  
              /**
              * CustomEvent fired after the modality mask is hidden
              * @event hideMaskEvent
              */
              this.hideMaskEvent = this.createEvent(EVENT_TYPES.HIDE_MASK);
              this.hideMaskEvent.signature = SIGNATURE;
  
              /**
              * CustomEvent when the Panel is dragged
              * @event dragEvent
              */
              this.dragEvent = this.createEvent(EVENT_TYPES.DRAG);
              this.dragEvent.signature = SIGNATURE;
          }
docs: Initializes the custom events for Module which are fired
  automatically at appropriate times by the Module class.