ngAfterViewInit.ts

@Component()
export class SomeComponent implements AfterViewInit {

  @ViewChild(RouterOutlet)
  outlet: RouterOutlet;

   
  ngAfterViewInit (): void {
    if (this.outlet.isActivated) {
      this.doSomethingWithComponent(this.outlet.component);
    }
    this.outlet.activateEvents
      .subscribe(component => this.doSomethingWithComponent(component))
    ;
  }

}