我想使用 SockJs 从服务器端接收 stomp 发布的所有事件。我已创建 WebSocketController。它在 app.js 中启动为

.controller('webSocketController', webSocketController)

WebSocketController.js

class WebSocketController {

  constructor($rootScope, $scope) {
   Object.assign(this, {$rootScope, $scope});
    this.onConnected = this.onConnected.bind(this);
    this.stompClient = '';
    let vm = this;

    setTimeout(function () {
            vm.connect();
    }, 2000);
  }

  onConnected(frame) {
    console.log('Connected: ' + frame);
    this.stompClient.subscribe('/topic/public', this.showMessage);
  }

  onError(error) {
      console.log("Could not connect to WebSocket server. Please refresh this page to try again!");
      console.log("error: ", error);
  }

  connect() {
    var socket = new SockJS('/ws');
    this.stompClient = Stomp.over(socket);
    this.stompClient.connect({}, this.onConnected, this.onError);
  }

  showMessage(message) {
      console.log("message received: ",message);
      $rootScope.$broadcast('refreshAccessPointList');
  }

  getStompClient() {
    return this.stompClient;
  }

}

var MyController = new WebSocketController();
MyController.$inject = ['$scope', '$rootScope'];
export default MyController;

当 showMessage() 尝试广播收到的事件时，无法找到 $rootScope。 控制台显示：Uncaught ReferenceError：$rootScope 未在 l 处定义 (webSocket.controller.js?eaab:33) 知道我遗漏了什么吗？