Angular2路由在http服务请求后导航到同一页面

Question

在我的Angular2项目中，我正在显示一个用户列表，我有一个添加按钮，当我添加新用户而不刷新页面时，我想将新添加的用户显示给我当前显示的用户列表。我来了以下解决方案，但在我的subscriber.component.ts文件中我调用this.getSubscribers（）;函数两次，第一次给出空指针异常。可能是什么解决方案？除了我目前用于显示而没有刷新的内容之外，还有其他方法吗？ 这是我的代码..

subscriber.component.html

<tr *ngFor="let subscriber of mf.data">
          <td>{{subscriber.name}}</td>
          <td>{{subscriber.email}}</td>
          <td>{{subscriber.mdn}}</td>
          <td class="text-center">
            <md-icon (click)="goToSubscriberDetails(subscriber)" mdTooltip="View Details">
              remove_red_eye
            </md-icon>
            <md-icon mdTooltip="Edit" (click)="openEditDialog(subscriber)">edit</md-icon>
            <md-icon mdTooltip="Recharge" (click)="rechargeDialog(subscriber)">attach_money</md-icon>
          </td>
        </tr>

subscriber.component.ts

 ngOnInit(): void {
    this.currentPage = 1;
    this.pageStart = 0;
    this.subscriberService
      .getSubscribers(0, 10, this.currentPage).subscribe(data => {
      this.subscribers = data.data;
      this.totalSubscriberLength = data.total;
    });
    this.sharedService.notifySubscriberObservable$.subscribe((res) => {
      this.getSubscribers();  // null pointer exception
      this.getSubscribers();
      console.log("in Subscriber template refresh")
    });
  }

adddialog.component.ts

 this.subscriberService.addSubscriber(data).subscribe(data => {
      let responseJson=data.json();
      if (responseJson.success)
      {
        this.toasterService.pop('success', 'SUCCESS', SUBSCRIBER_ADD_SUCCESS_MESSAGE);
        this.sharedService.notifyOtherSubscriber();
      }

      else
        this.toasterService.pop('error', 'FAILED',SUBSCRIBER_ADD_FAILURE_MESSAGE);
    }

global.ts

private notify = new Subject<any>();
  notifyObservable$ = this.notify.asObservable();
  constructor(){}
  public notifyOther()
  {
    this.notify.next();
  }
  private notifySubscriber = new Subject<any>();
  notifySubscriberObservable$ = this.notifySubscriber.asObservable();
  public notifyOtherSubscriber() {
    this.notifySubscriber.next();
  }