两个Angular2组件之间的通信问题
我有2个Angular2组件,我希望能够共享一个值 我的应用程序组件代码是:两个Angular2组件之间的通信问题,angular,typescript,angular2-routing,angular-components,Angular,Typescript,Angular2 Routing,Angular Components,我有2个Angular2组件,我希望能够共享一个值 我的应用程序组件代码是: <app-header></app-header> <router-outlet></router-outlet> <app-footer></app-footer> 最后,我的标题组件视图是: <div id="wrapper"> <section> <div id="topHeader">
<app-header></app-header>
<router-outlet></router-outlet>
<app-footer></app-footer>
最后,我的标题组件视图是:
<div id="wrapper">
<section>
<div id="topHeader">
<div class="oLogo">
<img id="OLogoImg" src="../../assets/images/Luceco-O-Logo-Transparent.png" alt="o-logo" height="20" />
</div>
</div>
</section>
</div>
<div class="container body-content">
<div id="header">
<div class="pageWrap">
<a id="logo" >
<img id="logoImg" src="../../assets/images/Luceco-Logo-Transparent.png" alt="logo" height="28" />
</a>
<ul id="menu">
<li id="home-menu" class="top-level home-menu">
<a href="#">Home</a>
</li>
<--FOLLOWING COMPONENT NEEDS TO BE DISPLAYED AFTER LOGIN -->
<li *ngIf="currentUser != null" id="logout-menu" class="top-level logout-menu">
<a href="#" (click)="logout()">Log Out</a>
</li>
</ul>
</div>
</div>
登录服务:
import { Injectable } from '@angular/core';
import { Http, Headers, RequestOptions, Response } from '@angular/http';
import { Router } from '@angular/router';
import 'rxjs/rx';
import { ConnectableObservable } from 'rxjs/rx';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
import { Observable } from 'rxjs/Observable';
import { User } from '../models/user';
@Injectable()
export class LoginService {
private authApiUrl = 'http://192.168.1.201/ForkliftHelperAPI/api/Auth';
private loginBehaviourSubject = new BehaviorSubject<boolean>(false);
public loginObservable = this.loginBehaviourSubject.asObservable();
constructor(private router: Router,
private _http: Http) { }
loginStatusChange(isLoggedIn: boolean) {
this.loginBehaviourSubject.next(isLoggedIn);
}
login(user: User): ConnectableObservable<any> {
let result: User;
const body = JSON.stringify(user);
const headers = new Headers({
'Content-Type': 'application/json'
});
const options = new RequestOptions({
headers: headers
});
const obsResponse = this._http.post(this.authApiUrl, body, options)
.map(res => res.json())
.publish();
obsResponse.subscribe(
(res: User) => {
result = res;
if (result) {
user.securityGroups = result.securityGroups;
sessionStorage.setItem('user', JSON.stringify(user));
this.router.navigate(['home']);
}
},
err => console.log(err)
);
return obsResponse;
}
logout() {
sessionStorage.removeItem('user');
this.router.navigate(['login']);
}
getCurrentUser() {
const storedUser = JSON.parse(sessionStorage.getItem('user'));
if (!storedUser) {
return null;
}
return new User(storedUser.username, storedUser.password, storedUser.securityGroups);
}
isLoggedIn() {
if (this.getCurrentUser() === null) {
this.router.navigate(['login']);
}
}
}
从'@angular/core'导入{Injectable};
从'@angular/Http'导入{Http,Headers,RequestOptions,Response};
从'@angular/Router'导入{Router};
进口“rxjs/rx”;
从'rxjs/rx'导入{ConnectableObservable};
从'rxjs/BehaviorSubject'导入{BehaviorSubject};
从“rxjs/Observable”导入{Observable};
从“../models/User”导入{User};
@可注射()
导出类登录服务{
私有authApiUrl=http://192.168.1.201/ForkliftHelperAPI/api/Auth';
private loginBehaviourSubject=新行为Subject(false);
public loginObservable=this.loginBehaviourSubject.asObservable();
构造函数(专用路由器:路由器、,
私有http:http){}
loginStatusChange(isLoggedIn:boolean){
this.loginBehaviourSubject.next(isLoggedIn);
}
登录(用户:用户):可连接可观察{
让结果:用户;
const body=JSON.stringify(用户);
const headers=新的头({
“内容类型”:“应用程序/json”
});
const options=新请求选项({
标题:标题
});
const obsResponse=this.\u http.post(this.authApiUrl,body,options)
.map(res=>res.json())
.publish();
obsResponse.subscribe(
(res:User)=>{
结果=res;
如果(结果){
user.securityGroups=result.securityGroups;
setItem('user',JSON.stringify(user));
this.router.navigate(['home']);
}
},
err=>console.log(err)
);
返回响应;
}
注销(){
sessionStorage.removietem('user');
this.router.navigate(['login']);
}
getCurrentUser(){
const storedUser=JSON.parse(sessionStorage.getItem('user');
if(!storedUser){
返回null;
}
返回新用户(storedUser.username、storedUser.password、storedUser.securityGroups);
}
伊斯洛格丁(){
if(this.getCurrentUser()==null){
this.router.navigate(['login']);
}
}
}
因此,基本上我的问题是,当LoginComponent的登录方法完成时,我希望它在HeaderComponent中设置currentUser变量,以便在路由器出口生成下一页时,标头正确显示注销按钮。如果在重定向后手动刷新页面,则更新会正确进行。但是,重定向时不会刷新页眉,只刷新路由器出口的内容
我尝试过使用服务,也尝试过使用@Input()和@Output(),但没有成功,可能是我用错了
我的主要问题似乎是,当重定向和导航发生时,页眉和页脚组件不会刷新,因为只有
中的组件受到影响。我这样做是为了避免在每个其他组件中都有页眉和页脚组件,但如果这是实现我所需要的唯一方法,那就这样吧
任何帮助都将不胜感激。首先,向根模块提供
登录服务
,而不是在标题和登录组件中提供
@NgModule({
// other things
providers: [LoginService,..........],
bootstrap: [AppComponent]
})
export class AppModule { }
对于这种组件到组件的通信,必须使用eventemiter
或RxjsBehaviorSubject
通常,更改一个组件中的任何值不会触发其他组件中的更改,除非您明确通知angular这样做。
有两种机制可以实现这一点
最好的方法是使用RxJs或用于此目的
您可以在登录服务
中创建行为主题
,步骤如下:
登录服务类:
import 'rxjs/add/operator/do';
import 'rxjs/add/operator/share';
export class LoginService {
private loginbehaviorSubject = new BehaviorSubject<boolean>(true);
public loginObservable$ = this.loginbehaviorSubject.asObservable();
loginStatusChange(isLoggedIn: boolean){
this.loginbehaviorSubject.next(isLoggedIn);
}
login(user: User): ConnectableObservable<any> {
let result: User;
const body = JSON.stringify(user);
const headers = new Headers({
'Content-Type': 'application/json'
});
const options = new RequestOptions({
headers: headers
});
return this._http.post(this.authApiUrl, body, options)
.map(res => res.json())
.do( (res: User) => {
result = res;
if (result) {
user.securityGroups = result.securityGroups;
sessionStorage.setItem('user', JSON.stringify(user));
}
},
err => console.log(err)
)
.share();
}
removeUserFromSession(){
if(sessionStorage.getItem('user')){
sessionStorage.removeItem('user');
}
}
logout() {
this.removeUserFromSession();
this.router.navigate(['login']);
}
}
在HeaderComponent中:
export class HeaderComponent implements OnInit {
public currentUser: string;
constructor(private loginService: LoginService) { }
ngOnInit() {
const currentUser = this.loginService.getCurrentUser();
if (currentUser !== null) {
this.currentUser = currentUser.username;
}
this.loginService.loginObservable$
.subscribe( (isStatusChanged) => {
const currentUser = this.loginService.getCurrentUser();
this.currentUser = currentUser.username;
});
}
logout() {
this.loginService.logout();
this.loginService.loginStatusChange(true); // notice this line
}
}
您应该使用EventBus,创建一个单例服务,它必须是主模块中的一个提供程序,而不是将其作为另一个地方的提供程序
这个想法是:
login.component.ts
constructor(public eventBus: EventBus) {}
onLoginSuccess(currentUser: any): void {
this.eventBus.onLoginSuccess.next(currentUser);
}
constructor(public eventBus: EventBus) {
this.eventBus.onLoginSuccess.subscribe((currentUser: any) => this.currentUser = currentUser);
}
header.component.ts
constructor(public eventBus: EventBus) {}
onLoginSuccess(currentUser: any): void {
this.eventBus.onLoginSuccess.next(currentUser);
}
constructor(public eventBus: EventBus) {
this.eventBus.onLoginSuccess.subscribe((currentUser: any) => this.currentUser = currentUser);
}
eventbus.service.ts
@Injectable()
export class EventBus {
onLoginSuccess: Subject<any> = new Subject();
}
@Injectable()
导出类事件总线{
onloginsucess:Subject=newsubject();
}
当然,您必须处理订阅和其他一切,这只是一个操作
用户完成登录后,eventBus
将使用onloginsucess
事件点击标题组件
@Injectable()
export class LoginService {
static instance: LoginService;
constructor() {
return LoginService.instance = LoginService.instance || this;
}
}
将此单例服务包括到route oulet组件和header组件。
在header component中,您可以使用ngOnChanges或ngDoCheck方法查看登录服务中的变量,一旦其值更改,函数中的代码将执行而不刷新
ngOnChanges(更改:SimpleChanges){}
ngDoCheck(){}
如果您能进行复制以查看您所做的一切,我们将不胜感激。是的,服务不用于@Input
/@Output
,这是为了在父/子组件之间建立通信。让服务持有currentUser
,并使用getter/setter管理其状态。然后,您的组件应该通过依赖项注入从getter使用此数据。在您的LoginService
中声明一个rxjsSubject
,并使用它来发出currentUser
,订阅它<
@Injectable()
export class LoginService {
static instance: LoginService;
constructor() {
return LoginService.instance = LoginService.instance || this;
}
}