Javascript 订阅角度错误
我正在尝试解决这个问题,因为我无法登录我的应用程序。 我在关注youtube教程,因为我是angular的新手。 这是所有者的github及其项目-> 它给了我以下错误: chat.service.ts的代码:Javascript 订阅角度错误,javascript,angular,subscribe,Javascript,Angular,Subscribe,我正在尝试解决这个问题,因为我无法登录我的应用程序。 我在关注youtube教程,因为我是angular的新手。 这是所有者的github及其项目-> 它给了我以下错误: chat.service.ts的代码: import { Injectable } from '@angular/core'; import { AngularFireDatabase, FirebaseListObservable } from 'angularfire2/database'; import { Angu
import { Injectable } from '@angular/core';
import { AngularFireDatabase, FirebaseListObservable } from 'angularfire2/database';
import { AngularFireAuth } from 'angularfire2/auth';
import { Observable } from 'rxjs/Observable';
import { AuthService } from '../services/auth.service';
import * as firebase from 'firebase/app';
import { ChatMessage } from '../models/chat-message.model';
@Injectable()
export class ChatService {
user: firebase.User;
chatMessages: FirebaseListObservable<ChatMessage[]>;
chatMessage: ChatMessage;
userName: Observable<string>;
constructor(
private db: AngularFireDatabase,
private afAuth: AngularFireAuth
) {
this.afAuth.authState.subscribe(auth => {
if (auth !== undefined && auth !== null) {
this.user = auth;
}
this.getUser().subscribe(a => {
this.userName = a.displayName;
});
});
}
getUser() {
const userId = this.user.uid;
const path = `/users/${userId}`;
return this.db.object(path);
}
getUsers() {
const path = '/users';
return this.db.list(path);
}
sendMessage(msg: string) {
const timestamp = this.getTimeStamp();
const email = this.user.email;
this.chatMessages = this.getMessages();
this.chatMessages.push({
message: msg,
timeSent: timestamp,
userName: this.userName,
email: email });
}
getMessages(): FirebaseListObservable<ChatMessage[]> {
// query to create our message feed binding
return this.db.list('messages', {
query: {
limitToLast: 25,
orderByKey: true
}
});
}
getTimeStamp() {
const now = new Date();
const date = now.getUTCFullYear() + '/' +
(now.getUTCMonth() + 1) + '/' +
now.getUTCDate();
const time = now.getUTCHours() + ':' +
now.getUTCMinutes() + ':' +
now.getUTCSeconds();
return (date + ' ' + time);
}
}
您应该使用this.chat,而不仅仅是在构造函数内部聊天
constructor(chat: ChatService) {
this.chat.getUsers().subscribe(users => {
this.users = users;
});
}
您是否在app.module.ts文件中导入了
聊天服务
,并将其添加到提供商
import { ChatService } from './services/chat.service';
@NgModule({
declarations: [
...
],
imports: [
...
],
providers: [
...
ChatService
],
bootstrap: [AppComponent]
})
export class AppModule { }
如果是这样,请尝试在构造函数中的chat
之前添加private
constructor(private chat: ChatService) {
chat.getUsers().subscribe(users => {
this.users = users;
});
}
同时显示您的用户列表组件,它是发生错误的地方。@GabrielBitencourt完成。我添加了valuechanges();这似乎是固定的,但只有一个文件。你仍然没有回答我的问题!错误是什么对不起,它生成了一个新错误->类型“AngularFireObject”上不存在属性“subscribe”。在chat.service.ts.So中,我应该保留valuechanges()?
返回这个.db.object(路径)
返回的是一个AngularFireObject
,而不是一个可观察的,所以是的。此外,还应该为函数定义返回类型,如getUser():AngularFireObject{
,以便IDE可以尽早捕获任何错误。(需要在顶部导入User
)
constructor(private chat: ChatService) {
chat.getUsers().subscribe(users => {
this.users = users;
});
}