Angular 2 : Loading components dynamically from a service response

Question

我知道这不是最好的解决方案，但我希望能够从 JSON 响应动态加载组件，大致如下:

应用组件

@Component({
    selector: 'my-app',
    template: '<h1>My First Angular 2 App</h1> {{component.title}} {{component.selector}}',
    providers: [AppService],
    directives: [ExampleComponent]
})
export class AppComponent implements OnInit {

    component:{};

    constructor(
        private _appService: AppService) {
    }

    ngOnInit() {
        this.component = this._appService.getComponent();
    }
}

应用服务

@Injectable()
export class AppService {

    component = {
        title: 'Example component',
        selector: '<example></example>'
    }

    getComponent() {
        return this.component;
    }
}

示例组件

@Component({
    selector: 'example',
    template: 'This a example component'
})
export class ExampleComponent  {
}

如果我运行这个例子，我的输出是<example></example>但它实际上并不渲染组件。我也试过使用 [innerHtml]="component.selector" ，但这也没有用。有没有人有想法或建议？

Answer 1

更新

创建组件的代码发生了一些变化。 可以在 Angular 2 dynamic tabs with user-click chosen components 中找到一个工作示例

---

要动态插入组件，您可以使用 ViewContainerRef.createComponent()

对于声明式方法，您可以使用辅助组件，例如

@Component({
  selector: 'dcl-wrapper',
  template: `<div #target></div>`
})
export class DclWrapper {
  @ViewChild('target', {read: ViewContainerRef}) target;
  @Input() type;
  cmpRef:ComponentRef;
  private isViewInitialized:boolean = false;

  constructor(private resolver: ComponentResolver) {}

  updateComponent() {
    if(!this.isViewInitialized) {
      return;
    }
    if(this.cmpRef) {
      this.cmpRef.destroy();
    }
   this.resolver.resolveComponent(this.type).then((factory:ComponentFactory<any>) => {
      this.cmpRef = this.target.createComponent(factory)
    });
  }

  ngOnChanges() {
    this.updateComponent();
  }

  ngAfterViewInit() {
    this.isViewInitialized = true;
    this.updateComponent();  
  }

  ngOnDestroy() {
    if(this.cmpRef) {
      this.cmpRef.destroy();
    }    
  }
}

另见 Angular 2 dynamic tabs with user-click chosen components

在你的例子中你可以像这样使用它

@Component({
    selector: 'my-app',
    template: '<h1>My First Angular 2 App</h1> {{component.title}} <dcl-wrapper [type]="component.type"></dcl-wrapper>',
    providers: [AppService],
    directives: [ExampleComponent]
})
export class AppComponent implements OnInit {

    component:{};

    constructor(
        private _appService: AppService) {
    }

    ngOnInit() {
        this.component = this._appService.getComponent();
    }
}

import {ExampleComponent} from './example.component.ts';

@Injectable()
export class AppService {

    component = {
        title: 'Example component',
        type: ExampleComponent
    }

    getComponent() {
        return this.component;
    }
}