Dom不更新新数据

Question

我正在尝试使用websockets设置一个简单的通知系统。

我的websocket服务:

import {Injectable} from '@angular/core';
import {Observable, Observer, Subject} from 'rxjs/Rx'
@Injectable()
export class WebSocketService {
  private socket: Subject<MessageEvent>;
  public connect(url): Subject<MessageEvent> {
    if (!this.socket) {
      this.socket = this.create(url);
    }
    return this.socket;
  }
  private create(url): Subject<MessageEvent> {
    let ws = new WebSocket(url);
    let observable = Observable.create(
      (obs: Observer<MessageEvent>) => {
        ws.onmessage = obs.next.bind(obs);
        ws.onerror = obs.error.bind(obs);
        ws.onclose = obs.complete.bind(obs);
        return ws.close.bind(ws);
      }
    );
    let observer = {
      next: (data: Object) => {
        if (ws.readyState === WebSocket.OPEN) {
          ws.send(JSON.stringify(data));
        }
      },
    };
    return Subject.create(observer, observable);
  }
}

通知服务包含以下通知:

import {Injectable} from '@angular/core';
import {Subject} from 'rxjs/Rx'
import {WebSocketService} from "./websocket.service";
@Injectable()
export class NotificationService {
  public messages: Subject<Object>;
  constructor(wsService: WebSocketService) {
    let notificationUrl = `ws://localhost:4969/Notification`;
    this.messages = <Subject<Object>>wsService
      .connect(notificationUrl)
      .map((response: MessageEvent): Object => {
        return JSON.parse(response.data);
      });
  }
}

订阅服务通知主题的组件:

import {Component, OnInit, ElementRef} from '@angular/core';
import {Notification} from "./notification";
import {NotificationService} from "../../services/notification.service";
@Component({
  selector: 'notifier',
  templateUrl: 'notifier.component.html',
  styleUrls: ['notifier.component.css'],
  host: {
    '(document:click)': 'onClickedOutside($event)',
  },
})
export class NotifierComponent implements OnInit {
  notifications: Notification[] =[];
  constructor(private elementRef: ElementRef, private notificationService: NotificationService) {
  }

  ngOnInit() {
    this.notificationService.messages.subscribe(notification => {
      let not = new Notification(notification.title, notification.notificationTypes, notification.data);
      console.log(not);
      let index = this.notifications.findIndex(x=>x.title == not.title);
      if (index ==-1) {
        this.notifications.push(not);
      }
      else {
        this.notifications[index].data.progress=not.data.progress;
      }
      console.log(this.notifications)
    });
  }
}

所以我的websocket服务器发送通知，可以唯一地识别它的标题。如果标题已经存在于我的通知数组中，我更新它的进度，否则我推送它。

一切都很好，除了一件事。我的视图不会在每次通知更新时更新，但如果我点击任何地方，点击事件将重新渲染，我将看到进度上升。

我读过一些关于Angular2如何传播数据的文章，从我的阅读中我了解到，当你订阅一个主题时，它的数据发生了变化，它应该触发一个事件来重新渲染，但显然不是这样的。

我错过了什么?

Answer 1

我已经能够在这个问题的帮助下解决我的问题:如何在Angular 2中强制组件的重新渲染?

为进一步参考，这里是我在组件的订阅函数中添加的确切行:

this.applicationRef.tick();