在 Angular5 中将对象从一个组件移动到同级组件

Question

我正在开发一个列表应用程序，该应用程序将对象从一个组件传输到一个相同的同级组件。我还想在每次移动时将 move 属性减少 1。我在实际将所选项目推送到同级数组时遇到问题。

这是我的数据示例...

import { player } from "./player";
export const PLAYERS: player[] = [
{
index: 1,
photo: "../../assets/images/lonzo.jpeg",
name: "Lonzo Ball",
position: "G",
moves: 5
},
{
index: 2,
photo: "../../assets/images/Brook.jpeg",
name: "Brook Lopez",
position: "C",
moves: 5
},

这是我在服务文件中的内容...

import { Injectable } from "@angular/core";
import { BehaviorSubject } from "rxjs/BehaviorSubject";
import { Subject } from 'rxjs/Subject';
import { player } from "./player";
import { PLAYERS } from "./players";
import 'rxjs/add/observable/of';
import { Observable } from "rxjs/Observable";
import { of } from "rxjs/observable/of";
import { bench } from './bench';
import { RESERVES } from './RESERVES';
@Injectable()
export class DataService {
public players = <any>PLAYERS;
public bench = <any>RESERVES;

public getPlayers(): Observable<player[]> {
return Observable.of(this.players);
}
public getReserves(): Observable<bench[]> {
return Observable.of(this.bench);
}
addToReserves(data) {
this.bench.next(data);
}
addToStarter(data) {
this.players.next(data)
}
constructor() {}
}

这是我在starters.ts文件中的内容...

import { Component, OnInit } from "@angular/core";
import { DataService } from '../data.service'
import { player } from "../player";
@Component({
selector: "app-roster-box",
templateUrl: "./roster-box.component.html",
styleUrls: ["./roster-box.component.css"],
})
export class RosterBoxComponent implements OnInit {
moves: number = 5;
btnText: string = "Move to Bench";
players: Array<any>

constructor(public dataService: DataService) {}
getPlayers() : void {
this.dataService.getPlayers()
.subscribe(players => this.players = players);
}

ngOnInit() {
this.getPlayers();

}
moveToBench( data, i): void {
this.dataService.addToReserves(data)
// this.players.splice(i, 1);

}
}

最后是bench.ts文件的代码...

import { Component, OnInit } from '@angular/core';
import { DataService } from '../../app/data.service'
import { bench } from "../bench";
@Component({
selector: 'app-roster-bench',
templateUrl: './roster-bench.component.html',
styleUrls: ['./roster-bench.component.css']
})
export class RosterBenchComponent implements OnInit {
moves: number = 5;
btnText: string = "Make Starter";
reserves: Array<any>;
constructor(private dataService: DataService) { }
getReserves() : void {
this.dataService.getReserves()
.subscribe(reserves => this.reserves = reserves);
}
ngOnInit() {
this.getReserves();
// this.moveData();
}
makeStarter( data, i): void {
this.dataService.addToStarter(data)
// this.players.splice(i, 1);
}
}

我希望只需单击 html 中的按钮即可将所选播放器移动到同级组件。我在如何构建服务/可观察等方面遇到麻烦，因为这是我第一次使用 Angular。

Answer 1

我有一点空闲时间...所以我将您的示例代码移动到此处的堆栈闪电战中：https://stackblitz.com/edit/angular-j2l8pq

我不确定你到底想完成什么，但试图基本上回答你的问题。

几个关键事项：

1)我假设板凳和球员阵列都需要是Player型。这允许您在两个数组之间移动相同类型的项，而不会丢失任何属性。

2)我将组件中的属性更改为getter。这样，它将始终从服务中获取当前值：

get players(): Player[] {
return this.dataService.players;
}
get bench(): Player[] {
return this.dataService.bench;
}

3)您似乎不需要主题/行为主题，所以我删除了导入。

我不确定你指的是什么"兄弟组件"。但是，如果您创建另一个与同一服务通信的组件，如果它也有如上所示的 getter，它将共享与播放器组件相同的数据。

希望提供的代码为您提供回答问题的基本方向。

元件

import { Component, OnInit } from "@angular/core";
import { DataService } from './player.service'
import { Player } from "./player";
@Component({
selector: 'app-roster-box',
template: 
`<div>Current Roster</div>
<li *ngFor="let player of players" (click)="moveToBench(player)">
{{ player.name }}
</li>
<br>
<div>Bench</div>
<li *ngFor="let player of bench">
{{ player.name }}
</li>
`
})
export class RosterBoxComponent implements OnInit {
moves: number = 5;
btnText: string = "Move to Bench";
get players(): Player[] {
return this.dataService.players;
}
get bench(): Player[] {
return this.dataService.bench;
}
constructor(public dataService: DataService) {}
getPlayers() : void {
this.dataService.getPlayers()
.subscribe();
}
ngOnInit() {
this.getPlayers();
}
moveToBench( player ): void {
console.log(player);
this.dataService.addToReserves(player)
}
}

服务

import { Injectable } from "@angular/core";
import { Player } from "./player";
import { Observable } from "rxjs/Observable";
import { of } from "rxjs/observable/of";
@Injectable()
export class DataService {
players: Player[] = [];
bench: Player[] = [];
constructor() {}
getPlayers(): Observable<Player[]> {
this.players = [
{
index: 1,
photo: "../../assets/images/lonzo.jpeg",
name: "Lonzo Ball",
position: "G",
moves: 5
},
{
index: 2,
photo: "../../assets/images/Brook.jpeg",
name: "Brook Lopez",
position: "C",
moves: 5
}
]
return of(this.players);
}
getReserves(): Observable<Player[]> {
return of(this.bench);
}
addToReserves(player: Player) {
this.bench.push(player);
const index = this.players.indexOf(player);
if (index > -1)
this.players.splice(index, 1);
}
addToStarter(data) {
this.players.push(data)
}
}