Angular2：視圖不會在更改變量時更新

Question

我有一個簡單的組件，它封裝了一個router-outlet。我已經設置了一個簡單的服務，它發出一個事件。該事件由組件和更新變量捕獲，然後在視圖中更新[class]。

Sidebar.component.ts

import { Component, OnInit } from '@angular/core'; 
import { ROUTER_DIRECTIVES } from '@angular/router'; 
import { SidebarService } from '../sidebar.service'; 
import { Subscription } from 'rxjs/Subscription'; 

@Component({ 
    moduleId: module.id, 
    selector: 'app-sidebar', 
    templateUrl: 'sidebar.component.html', 
    styleUrls: ['sidebar.component.css'], 
    directives: [ROUTER_DIRECTIVES] 
}) 

export class SidebarComponent implements OnInit { 
    showSidebar:boolean = false; 
    subscription:Subscription; 

    constructor(public sidebarService: SidebarService) { 
    this.subscription = this.sidebarService.sidebarEvent$.subscribe(this.toggleSidebar); 
    } 

    ngOnInit() { 

    } 

    toggleSidebar (state) { 
    console.log(state); 
    this.showSidebar = state; 
    } 
} 

sidebar.service.ts

import { Injectable, EventEmitter } from '@angular/core'; 
import {BehaviorSubject} from 'rxjs/BehaviorSubject'; 

@Injectable() 
export class SidebarService { 

    private _sidebarEventSource = new BehaviorSubject<boolean>(false); 
    sidebarEvent$ = this._sidebarEventSource.asObservable(); 
    constructor() { } 

    open() { 
    this._sidebarEventSource.next(true); 
    } 

    close() { 
    this._sidebarEventSource.next(false); 
    } 

} 

我嘗試這樣：Angular2: view is not updated from inside a subscription。

Error: ORIGINAL EXCEPTION: TypeError: Cannot read property 'run' of undefined 

我用ng-cli腳手架我的應用程序。

不用說，我對angular2完全陌生，並且在ng1中擁有背景。所以這些編碼風格，對我來說是一個新的世界。

而且，順便說一句，謝謝你停下來。 :)

Answer 1

constructor(public sidebarService: SidebarService) { 
    this.subscription = this.sidebarService.sidebarEvent$.subscribe((data)=>{ 
     this.toggleSidebar(data); 
    }); 
}