javascript - Angular : No Error but not showing data in Material Table

Question

我的控制台没有错误，但无法在 Material 数据表中显示它。在代码中查看了一段时间，但无法弄清楚。我唯一想到的是 API 不对。 xxxxx 表示 API 的一些 URL。一律不允许我显示真实链接。

restaurant.service.ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';
import { Restaurant } from '../models/restaurant.model';

@Injectable({
  providedIn: 'root'
})
export class RestaurantService {
  private restaurantsUrl = 'https://xxxxxx/getAllServices.php';

  constructor(private http: HttpClient) { }

  getRestaurants(): Observable<Restaurant[]> {
    return this.http.get<Restaurant[]>(this.restaurantsUrl);
  }
}

餐厅表.component.ts

import { Component, ViewChild,OnInit } from '@angular/core';
import { RestaurantService } from '../services/restaurant.service';

import { Observable } from 'rxjs/Observable';
import 'rxjs/add/observable/of';
import {DataSource} from '@angular/cdk/collections';
import { Restaurant } from '../models/restaurant.model';


@Component({
  selector: 'app-restaurants-table',
  templateUrl: './restaurants-table.component.html',
  styleUrls: ['./restaurants-table.component.css']
})

export class RestaurantsTableComponent implements OnInit {

  dataSource = new RestaurantDataSource(this.restaurantService);
  displayedColumns = ['id', 'ime_restorana', 'opis', 'broj_telefona', 'adresa_restorana','edits'];

  constructor(private restaurantService: RestaurantService) {
}

  ngOnInit() {
  }

}

export class RestaurantDataSource extends DataSource<any> {

  constructor(private restaurantService: RestaurantService) {
    super();
  }

  connect(): Observable<Restaurant[]> {
    return this.restaurantService.getRestaurants();
  }

  disconnect() {}

}

restaurant-table.component.html

<div class="">
  <mat-table [dataSource]="dataSource">

    <ng-container matColumnDef="id">
      <mat-header-cell *matHeaderCellDef> ID </mat-header-cell>
      <mat-cell *matCellDef="let restaurant"> {{ restaurant.id }} </mat-cell>
    </ng-container>

    <ng-container matColumnDef="ime_restorana">
      <mat-header-cell *matHeaderCellDef> Naziv </mat-header-cell>
      <mat-cell *matCellDef="let restaurant"> {{ restaurant.ime_restorana }} </mat-cell>
    </ng-container>

    <ng-container matColumnDef="opis">
      <mat-header-cell *matHeaderCellDef> Opis </mat-header-cell>
      <mat-cell *matCellDef="let restaurant"> {{ restaurant.opis }} </mat-cell>
    </ng-container>

    <ng-container matColumnDef="broj_telefona">
      <mat-header-cell *matHeaderCellDef> Broj Telefona </mat-header-cell>
      <mat-cell *matCellDef="let restaurant"> {{ restaurant.broj_telefona }} </mat-cell>
    </ng-container>

    <ng-container matColumnDef="adresa_restorana">
      <mat-header-cell *matHeaderCellDef> Adresa </mat-header-cell>
      <mat-cell *matCellDef="let restaurant"> {{ restaurant.adresa_restorana }} </mat-cell>
    </ng-container>

    <ng-container matColumnDef="edits">
      <th mat-header-cell *matHeaderCellDef></th>   
      <td mat-cell *matCellDef="let element"> 
        <button mat-raised-button class="edit-btn"><mat-icon>edit</mat-icon></button> 
        <button mat-raised-button class="edit-btn"><mat-icon>remove_red_eye</mat-icon></button> 
      </td>
    </ng-container>

    <mat-header-row *matHeaderRowDef="displayedColumns"></mat-header-row>
    <mat-row *matRowDef="let row; columns: displayedColumns;"></mat-row>

  </mat-table>
</div>

和 user.model.ts

export interface User {
    name: string;
    email: string;
    phone: string;
    company: {
        name: string;
    }
}

Answer 1

您当前的 dataSource 是 RestaurantDataSource 类的实例，您想要的(我想)是餐厅的实际列表，因此

dataSource = new RestaurantDataSource(this.restaurantService).connect();

但是，您的 connect() 方法返回一个 Observable，而不是列表本身，因此您需要在模板中使用 async 管道

<mat-table [dataSource]="dataSource | async">