从服务创建后销毁组件实例

Question

I'm creating components dynamic using a service. Component was created, but the ngOnDestroy lifecycle look is not getting called.

Below is my service file code.

@Injectable()
export class CreateComponentService implements OnDestroy {
  private rootViewContainer: ViewContainerRef;
  private componentFactory: ComponentFactory<any>;
  private componentReference;
  constructor(private componentFactoryResolver: ComponentFactoryResolver) {}

  setRootViewContainerRef(view: ViewContainerRef): void {
    this.rootViewContainer = view;
  }

  createComponent(content, type) {
    this.componentFactory = this.componentFactoryResolver.resolveComponentFactory(type);
    this.componentReference = this.rootViewContainer.createComponent(this.componentFactory);
    this.componentReference.instance.contentOnCreate(content);
  }

  ngOnDestroy() {
    // Destroy components to avoide memory leaks
    this.componentReference.destroy();
  }
}

In Component.ts

constructor(private service: CreateComponentService) {}

      data.forEach(response => {
        this.service.createComponent(response, type);
      });

Please show me the best way to destroy the component instance

Answer 1

You don't explicitly destroy the service, and the service onDestroy method won't be called.

You can try to detach the views from the change-detection tree, which is similar to what you need,

private insertComponent(componentType): void {
    const factory = this.factoryResolver.resolveComponentFactory(componentType);
    var containerRef = this.rootViewContainer.createComponent(factory);
    // always get the most recently appended node
    var viewRef = this.rootViewContainer.get(this.rootViewContainer.length - 1);
    viewRef.detach();
    containerRef = null;
}

containerRef will be garbage collected eventually. And since you detach the view, it will behave like static content. Note that if you destroy containerRef , the associated view/html will also get destroyed.

update: demo https://stackblitz.com/edit/dynamic-component-example-swrj8j?file=src/app/service-based/factory.service.ts