[英]Angular component isnt passing data before the child component is loaded
在我的代码中,我有一个组件保存从 firebase 检索到的所有数据。 包括一个名为“currentTurnName”的变量,它从父组件传递到子组件。 该变量用于在子组件内呈现抽搐通道,但不会在数据更改时更新。我遵循了一些堆栈溢出指南,讨论了使用 *ngIf 指令(如 <childComponent *ngIf"currentTurnName"> 停止子组件从加载到检索到数据 - 它在页面加载时工作,除非当该变量异步传递新数据时它不起作用。
子组件
export class TwitchVideoComponent implements OnInit {
constructor() {
}
player: any;
@Input() currentTurnName: any;
ngOnInit(): void {
var options = {
width: 1080,
height: 720,
channel: this.currentTurnName,
};
this.player = new Twitch.Player("<player div ID>", options)
this.player.setVolume(0.5);
console.log(this.currentTurnName);
}
// ngOnChanges(changes: SimpleChanges) {
// if (this.currentTurnName) {
// this.player.setChannel(this.currentTurnName);
// }
// }
}
子模板
<div id="<player div ID>" class="twitch"></div>
父组件
export class GameRoomComponent implements OnInit {
public users$: Observable<User[]>
currentUser: Observable<CurrentUser[]>;
constructor(private usersService: UsersService, private afs: AngularFirestore) {
this.currentTurn = afs.collection<CurrentUser>('currentPlayerDB').valueChanges().pipe(
tap(res => {
this.currentTurnName = res[0].user;
console.log(this.currentTurnName);
})
).subscribe();
}
currentTurn: any;
items: any;
currentTurnName : any;
父模板
<app-twitch-video *ngIf="currentTurnName" [currentTurnName]="currentTurnName" >
这有点谈到我的问题,但考虑到数据已更改,我的问题更复杂Angular 2 子组件在通过@input() 传递数据之前加载
您可以使用 Angular 的属性设置器。 可以在本节中找到文档(使用 setter 拦截输入属性更改): https://angular.io/guide/component-interaction
这是使用您的代码的片段:
export class TwitchVideoComponent implements OnInit {
constructor() {}
player: any;
@Input() set currentTurnName(name) {
this._currentTurnName = name;
console.log('This should fire every time this Input updates', this._currentTurnName);
if (this._currentTurnName) {
this.player.setChannel(this._currentTurnName);
}
}
public _currentTurnName: any;
ngOnInit(): void {
var options = {
width: 1080,
height: 720,
channel: this._currentTurnName,
};
this.player = new Twitch.Player("<player div ID>", options)
this.player.setVolume(0.5);
console.log(this._currentTurnName);
}
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.