mxDragSource.prototype.removeListeners=function(){null!=this.eventSource&&(mxEvent.removeGestureListeners(this.eventSource,null,this.mouseMoveHandler,this.mouseUpHandler),this.eventSource=null);mxEvent.removeGestureListeners(document,null,this.mouseMoveHandler,this.mouseUpHandler);this.mouseUpHandler=this.mouseMoveHandler=null};