Angular2 Dynamic content loading throws Expression changed exception

Question

I\'m creating a generic Gantt visualization component.

The part where I will display the weeks and tasks is generic, but every row will have a header that I want to be d

Answer 1

The error says it all:

It seems like the view has been created after its parent and its children have been dirty checked. Has it been created in a change detection hook?

You've created component dynamically ("outside" of angular lifecycle), this means you need to control change detection manually.

So that is what you need to do:

1) After creating a component fire detectChanges() for it

2) Before disposing detach() change detection;

Here is example of my directive that creates component dynamically:

export class ValidationMessageDirective implements AfterViewInit, OnDestroy {

  private validationMessageComponent: ComponentRef = null;

  ngAfterViewInit(): void {
    let factory = this.componentFactoryResolver.resolveComponentFactory(this.vmComp);
    this.ngOnDestroy();
    this.validationMessageComponent = this.viewContainer.createComponent(factory, null, this.viewContainer.injector);
    this.validationMessageComponent.changeDetectorRef.detectChanges();
  }

  ngOnDestroy(): void {
    if (this.validationMessageComponent) {
      this.validationMessageComponent.changeDetectorRef.detach();
      //this.validationMessageComponent.destroy();
    }
  }

  constructor(
    private viewContainer: ViewContainerRef,
    private componentFactoryResolver: ComponentFactoryResolver,
    @Inject(ValidationMessageComponent) private vmComp: Type
  ) { }
}

Related issue: https://github.com/angular/angular/issues/11007