如何在 Angular 6 中观察服务变量

Question

我已经尝试 Angular 更新服务变量 "open_popup" 好几天了，但没有成功。

TLDR；我想做的是，每当变量 "open_popup" 发生变化时，让它在组件上发生变化，也能够从组件函数中更改服务变量。

这是我目前尝试过的方法。

app/src/app/audience-creator/shared/audience-creator.service.ts

import { Injectable } from "@angular/core";
import {Observable} from "rxjs/index";
import { of } from "rxjs/index";

@Injectable()
export class AudienceCreatorService {
    constructor(private http: HttpClient) {}

    public open_popup = false;

    public toggleCreatorPopup() {
        this.open_popup = !this.open_popup;
    }

    popupIsOpen(): Observable<any> {
        return of(this.open_popup);
    }
}

app/src/app/audience-creator/audience-creator.component.ts

import {Stuff} from "@angular/core";

@Component({
    selector: 'audience-creator',
    templateUrl: 'audience-creator.html'
})
export class AudienceCreatorComponent implements AfterViewInit, OnInit {

    public popup_is_open = false;

    @Input()
    audience_creator_service;

    ngOnInit() {
        this.audience_creator_service.popupIsOpen().subscribe(
            popup_is_open => this.popup_is_open = popup_is_open
        );
    }
}

app/src/app/audience-creator/audience-creator.html

--> {{ this.popup_is_open }} variable is always false.

不起作用

{{ this.popup_is_open }}

PS：只是试图将函数直接破解到模板中并且它起作用了所以我绑定组件变量的方式一定有问题？？

{{ audience_creator_service.popupIsOpen().value }}

Answer 1

@Injectable()
export class AudienceCreatorService {
constructor(private http: HttpClient) {}

public open_popup = false
private isOpen: BehaviorSubject<boolean> = new BehaviorSubject(false);

public toggleCreatorPopup() {
    this.open_popup = !this.open_popup;
    this.isOpen.next(this.open_popup);
}

popupIsOpen(): Observable<any> {
    return this.isOpen.asObservable();
}
}

如何在 Angular 6 中观察服务变量

How to watch service variable in Angular 6

typescript

angular

angular6