在 Angular Material 2 中将参数传递给 MdDialog

Question

我正在使用 Angular Material 2，我想用 MdDialog 打开一个对话框 window，它显示有关存储在 firebase 中的用户的一些信息。

@Injectable()
export class TweetService {

  dialogRef: MdDialogRef<TweetDialogComponent>;

  constructor(public dialog: MdDialog) {
  }

  sendTweet(viewContainerRef: ViewContainerRef) {
    let config = new MdDialogConfig();
    config.viewContainerRef = viewContainerRef;

    this.dialogRef = this.dialog.open(TweetDialogComponent, config);

    this.dialogRef.afterClosed().subscribe(result => {
      this.dialogRef = null;
    });
  }
}

@Component({
  selector: 'app-tweet-dialog',
  templateUrl: './tweet-dialog.component.html'
})
export class TweetDialogComponent implements OnInit {
  private user: FirebaseObjectObservable<any[]>;

  constructor(
    public dialogRef: MdDialogRef<TweetDialogComponent>,
    private usersService: UsersService,
    private authService: AuthService) { }

  ngOnInit() {
    let uid = this.authService.getUser().uid;
    this.user = this.usersService.getUser(uid);
  }

}

模板就这么简单

<h1>{{ (user | async)?.email }}</h1>

用户存储在 Firebase 中，问题是对话框 window 会在短时间内显示 null，直到检索到用户。所以我想，好吧，也许在 TweetService 中检索用户并将其作为参数传递给 TweetDialogComponent 是个好主意，但后来我意识到我不知道该怎么做。

我看到了这个所以我尝试了这个

@Injectable()
export class TweetService {

  private dialogRef: MdDialogRef<TweetDialogComponent>;
  private user: FirebaseObjectObservable<any[]>;

  constructor(
    private dialog: MdDialog,
    private usersService: UsersService,
    private authService: AuthService) {
  }

  getUser(): FirebaseObjectObservable<any[]> {
    return this.user;
  }

  sendTweet(viewContainerRef: ViewContainerRef) {
    let config = new MdDialogConfig();
    config.viewContainerRef = viewContainerRef;

    let uid = this.authService.getUser().uid;
    this.user = this.usersService.getUser(uid);

    this.dialogRef = this.dialog.open(TweetDialogComponent, config);

    this.dialogRef.afterClosed().subscribe(result => {
      this.dialogRef = null;
    });
  }
}

@Component({
  selector: 'app-tweet-dialog',
  templateUrl: './tweet-dialog.component.html'
})
export class TweetDialogComponent implements OnInit {
  private user: FirebaseObjectObservable<any[]>;

  constructor(
    public dialogRef: MdDialogRef<TweetDialogComponent>,
    private tweetService: TweetService) { }

  ngOnInit() {
    this.user = this.tweetService.getUser();
  }

}

但这给了我一个错误 Can't resolve all parameters for TweetDialogComponent: (MdDialogRef, ?).

知道怎么做吗？谢谢，

更新

这似乎与桶中的导入顺序有关，但我没有使用桶，我是直接从文件中导入的。这是我的 ngModule 声明（抱歉，有点长...）

@NgModule({
  declarations: [
    AppComponent,
    ProfileComponent,
    PeopleComponent,
    TimelineComponent,
    TweetDialogComponent,
    ProfilePipe
  ],
  entryComponents: [
    TweetDialogComponent
  ],
  imports: [
    routing,
    BrowserModule,
    AuthModule,
    AngularFireModule.initializeApp(firebaseConfig, firebaseAuthConfig),
    MaterialModule.forRoot()
  ],
  providers: [
    AUTH_PROVIDERS,
    AuthGuard,
    UsersService,
    { provide: TweetService, useClass: TweetService },
    { provide: LocationStrategy, useClass: HashLocationStrategy },
    { provide: APP_BASE_HREF, useValue: '/' }
  ],
  bootstrap: [ AppComponent ]
})
export class AppModule {
}

TweetService 在我的 AppComponent 中运行良好，因此提供程序应该没有问题。这是我的 TweetDialogComponent 中的导入顺序（我看不出有什么不对）。

import { Component, OnInit } from '@angular/core';
import { MdDialogRef } from '@angular/material/dialog';

import { FirebaseObjectObservable } from 'angularfire2';

import { TweetService } from '../../shared/services/tweet.service';

项目的结构（对于受影响的组件）是这样的：

src/app/
       /app.module.ts
       /app.component.ts
       /shared/services/
                       /tweet.service.ts
                       /users.service.ts
       /components/tweet-dialog/
                               /tweet-dialog.component.ts

Answer 1

您遇到了循环依赖。 (TweetDialogComponent --> TweetService --> TweetDialogComponent)

您可以通过使用摘要来解决 class:

基础-tweet.service.ts

import { ViewContainerRef } from '@angular/core';

export abstract class BaseTweetService {
  getUser() {};

  sendTweet(viewContainerRef: ViewContainerRef) {}
}

app.module.ts

{ provide: BaseTweetService, useClass: TweetService },

app.component.ts

constructor(
    ...
    private tweetService: BaseTweetService,

tweet-dialog.component.ts

constructor(
  ...
  private tweetService: BaseTweetService) {

tweet.service.ts

export class TweetService implements BaseTweetService {

另见

在 Angular Material 2 中将参数传递给 MdDialog

Pass parameter to MdDialog in Angular Material 2

angular

angular-material2