怎么带有用户点击选择组件的Angular 2动态标签?

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我正在尝试设置一个选项卡系统,允许组件注册自己(带有标题)。第一个选项卡就像一个收件箱,有大量的操作/链接项可供用户选择,并且每一次单击都应该能够实例化一个新组件。动作/链接来自JSON。

然后实例化的组件将自己注册为一个新的选项卡。

我不确定这是不是最好的方法?我见过的唯一指南是静态标签,这没有帮助。

到目前为止,我只得到了一个选项卡服务,这个选项卡服务是在Main中引导的,可以在整个应用程序中持久保存,看起来像这样。

export interface ITab { title: string; }

@Injectable()
export class TabsService {
    private tabs = new Set<ITab>();

    addTab(title: string): ITab {
        let tab: ITab = { title };
        this.tabs.add(tab);
        return tab;
    }

    removeTab(tab: ITab) {
        this.tabs.delete(tab);
    }
}

问题:

1)如何在收件箱中有一个动态列表来创建新的(不同的)选项卡?我猜会使用DynamicComponentBuilder吗?

(2)如何将从收件箱(点击)创建的组件注册为制表符并显示?

编辑:试着澄清

将收件箱看作是一个邮件收件箱,将条目作为JSON获取并显示多个条目。单击其中一个项后,将创建一个新的选项卡,该选项卡的操作为“type”。然后,类型是一个组件。

编辑2:图像

提问于
用户回答回答于

柱塞实例RC.7:

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

  constructor(private componentFactoryResolver: ComponentFactoryResolver, private compiler: Compiler) {}

  updateComponent() {
    if(!this.isViewInitialized) {
      return;
    }
    if(this.cmpRef) {
      // when the `type` input changes we destroy a previously 
      // created component before creating the new one
      this.cmpRef.destroy();
    }

    let factory = this.componentFactoryResolver.resolveComponentFactory(this.type);
    this.cmpRef = this.target.createComponent(factory)
    // to access the created instance use
    // this.compRef.instance.someProperty = 'someValue';
    // this.compRef.instance.someOutput.subscribe(val => doSomething());
  }

  ngOnChanges() {
    this.updateComponent();
  }

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

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

使用实例

// Use dcl-wrapper component
@Component({
  selector: 'my-tabs',
  template: `
  <h2>Tabs</h2>
  <div *ngFor="let tab of tabs">
    <dcl-wrapper [type]="tab"></dcl-wrapper>
  </div>
`
})
export class Tabs {
  @Input() tabs;
}
@Component({
  selector: 'my-app',
  template: `
  <h2>Hello {{name}}</h2>
  <my-tabs [tabs]="types"></my-tabs>
`
})
export class App {
  // The list of components to create tabs from
  types = [C3, C1, C2, C3, C3, C1, C1];
}
@NgModule({
  imports: [ BrowserModule ],
  declarations: [ App, DclWrapper, Tabs, C1, C2, C3],
  entryComponents: [C1, C2, C3],
  bootstrap: [ App ]
})
export class AppModule {}

这在Angular2RC.5中又发生了变化。

演示如何在RC.5中动态创建组件。

更新-使用ViewContainerRef.createComponent()

因为DynamicComponentLoader不建议使用,则需要再次更新该方法。

@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)
      // to access the created instance use
      // this.compRef.instance.someProperty = 'someValue';
      // this.compRef.instance.someOutput.subscribe(val => doSomething());
    });
  }

  ngOnChanges() {
    this.updateComponent();
  }

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

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

柱塞实例RC.4

柱塞例子Beta.17

UPDATE-使用loadNextToLocation

export class DclWrapper {
  @ViewChild('target', {read: ViewContainerRef}) target;
  @Input() type;
  cmpRef:ComponentRef;
  private isViewInitialized:boolean = false;

  constructor(private dcl:DynamicComponentLoader) {}

  updateComponent() {
    // should be executed every time `type` changes but not before `ngAfterViewInit()` was called 
    // to have `target` initialized
    if(!this.isViewInitialized) {
      return;
    }
    if(this.cmpRef) {
      this.cmpRef.destroy();
    }
    this.dcl.loadNextToLocation(this.type, this.target).then((cmpRef) => {
      this.cmpRef = cmpRef;
    });
  }

  ngOnChanges() {
    this.updateComponent();
  }

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

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

原版

Tabs组件获取传递的类型数组,并为数组中的每个项创建“选项卡”。

@Component({
  selector: 'dcl-wrapper',
  template: `<div #target></div>`
})
export class DclWrapper {
  constructor(private elRef:ElementRef, private dcl:DynamicComponentLoader) {}
  @Input() type;

  ngOnChanges() {
    if(this.cmpRef) {
      this.cmpRef.dispose();
    }
    this.dcl.loadIntoLocation(this.type, this.elRef, 'target').then((cmpRef) => {
      this.cmpRef = cmpRef;
    });
  }
}

@Component({
  selector: 'c1',
  template: `<h2>c1</h2>`

})
export class C1 {
}

@Component({
  selector: 'c2',
  template: `<h2>c2</h2>`

})
export class C2 {
}

@Component({
  selector: 'c3',
  template: `<h2>c3</h2>`

})
export class C3 {
}

@Component({
  selector: 'my-tabs',
  directives: [DclWrapper],
  template: `
  <h2>Tabs</h2>
  <div *ngFor="let tab of tabs">
    <dcl-wrapper [type]="tab"></dcl-wrapper>
  </div>
`
})
export class Tabs {
  @Input() tabs;
}


@Component({
  selector: 'my-app',
  directives: [Tabs]
  template: `
  <h2>Hello {{name}}</h2>
  <my-tabs [tabs]="types"></my-tabs>
`
})
export class App {
  types = [C3, C1, C2, C3, C3, C1, C1];
}

还有一种方法可以将数据传递给动态创建的组件,如:someData需要像type)

    this.dcl.loadIntoLocation(this.type, this.elRef, 'target').then((cmpRef) => {
  cmpRef.instance.someProperty = someData;
  this.cmpRef = cmpRef;
});

还有一些支持将依赖注入与共享服务一起使用。

用户回答回答于

有可供使用的组件(Rc5兼容)用Compiler将组件注入到步骤容器和服务,以便数据同步

    import { Directive , Input, OnInit, Compiler , ViewContainerRef } from '@angular/core';

import { StepsService } from './ng2-steps';

@Directive({
  selector:'[ng2-step]'
})
export class StepDirective implements OnInit{

  @Input('content') content:any;
  @Input('index') index:string;
  public instance;

  constructor(
    private compiler:Compiler,
    private viewContainerRef:ViewContainerRef,
    private sds:StepsService
  ){}

  ngOnInit(){
    //Magic!
    this.compiler.compileComponentAsync(this.content).then((cmpFactory)=>{
      const injector = this.viewContainerRef.injector;
      this.viewContainerRef.createComponent(cmpFactory, 0,  injector);
    });
  }

}

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