angular 4+ assign @Input for ngComponentOutlet dyn

2020-01-28 05:27发布

问题:

In Angular 4 to dynamically create a component you can use ngComponentOutlet directive: https://angular.io/docs/ts/latest/api/common/index/NgComponentOutlet-directive.html

something like this:

Dynamic component

@Component({
  selector: 'dynamic-component',
  template: `
     Dynamic component
  `
})
export class DynamicComponent {
  @Input() info: any;
}

App

@Component({
  selector: 'my-app',
  template: `
     App<br>
     <ng-container *ngComponentOutlet="component"></ng-container>
  `
})
export class AppComponent {
  this.component=DynamicComponent;
}

How do I pass @Input() info: any; information in this template <ng-container *ngComponentOutlet="component"></ng-container> ?

回答1:

Such a feature was discussed in the pull request for ngComponentOutlet but was dropped for now. Even the componentRef shown currently in https://angular.io/docs/ts/latest/api/common/index/NgComponentOutlet-directive.html is not public and therefore not available https://github.com/angular/angular/blob/3ef73c2b1945340ca6bd21f1790260c88698ae26/modules/%40angular/common/src/directives/ng_component_outlet.ts#L78

I'd suggest you create your own directive derived from https://github.com/angular/angular/blob/3ef73c2b1945340ca6bd21f1790260c88698ae26/modules/%40angular/common/src/directives/ng_component_outlet.ts#L72

and assign values to inputs like shown in Angular 2 dynamic tabs with user-click chosen components

this.compRef.instance.someProperty = 'someValue';


回答2:

With the help of the post of @Günter Zöchbauer I solved a similar problem this way - I hope you can adapt it somehow.

First I defined some interfaces:

// all dynamically loaded components should implement this guy
export interface IDynamicComponent { Context: object; }

// data from parent to dynLoadedComponent
export interface IDynamicComponentData {
  component: any;
  context?: object;
  caller?: any;
}

then I implemented them inside of the dynamically loaded component

dynamicLoadedComponentA.ts

// ...
export class DynamicLoadedComponentA implements IDynamicComponent {
// ...

// data from parent
public Context: object;

// ...

After that I built a new component which is responsible for the magic. Important here is that I had to register all dyn. loaded components as entryComponents.

dynamic.component.ts

@Component({
  selector: 'ngc-dynamic-component',
  template: ´<ng-template #dynamicContainer></ng-template>´,
  entryComponents: [ DynamicLoadedComponentA ]
})
export class DynamicComponent implements OnInit, OnDestroy, OnChanges {
  @ViewChild('dynamicContainer', { read: ViewContainerRef }) public dynamicContainer: ViewContainerRef;

  @Input() public componentData: IDynamicComponentData;

  private componentRef: ComponentRef<any>;
  private componentInstance: IDynamicComponent;

  constructor(private resolver: ComponentFactoryResolver) { }

  public ngOnInit() {
    this.createComponent();
  }

  public ngOnChanges(changes: SimpleChanges) {
    if (changes['componentData']) {
      this.createComponent();
    }
  }

  public ngOnDestroy() {
    if (this.componentInstance) {
      this.componentInstance = null;
    }
    if (this.componentRef) {
      this.componentRef.destroy();
    }
  }

  private createComponent() {
    this.dynamicContainer.clear();
    if (this.componentData && this.componentData.component) {
      const factory: ComponentFactory<any> = this.resolver.resolveComponentFactory(this.componentData.component);
      this.componentRef = this.dynamicContainer.createComponent(factory);
      this.componentInstance = this.componentRef.instance as IDynamicComponent;

      // fill context data
      Object.assign(this.componentInstance.Context, this.componentData.context || {});

      // register output events
      // this.componentRef.instance.outputTrigger.subscribe(event => console.log(event));
    }
  }
}

here the usage of this shiny new stuff:

app.html

<!-- [...] -->
<div>
  <ngc-dynamic-component [componentData]="_settingsData"></ngc-dynamic-component>
</div>
<!-- [...] -->

app.ts

// ...
  private _settingsData: IDynamicComponent = {
    component: DynamicLoadedComponentA,
    context: { SomeValue: 42 },
    caller: this
  };
// ...


回答3:

I think for now you can use

https://www.npmjs.com/package/ng-dynamic-component

It is made specifically for this issue