Тестирование subscribe

import { Component, ViewChild, OnInit } from '@angular/core';
import { HeaderComponent } from './header/header.component';
import { Day, Time } from './day';
import { DayDashboardComponent } from './day-dashboard/day-dashboard.component';
import { Router  } from '@angular/router';
import { ChangeComponent } from './change/change.component';
 
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  forTest: boolean;
 
  @ViewChild(HeaderComponent)
    private headerComponent: HeaderComponent;
 
  constructor(private router: Router) {}
 
  routChanged(obj) {
      if (obj instanceof DayDashboardComponent) {
        obj.Clicked.subscribe(day =>
          this.headerComponent.setDay(day));
        this.headerComponent.Today
          .subscribe(() => obj.clear());
        this.forTest = true;
      }
      else {
        this.forTest = false;
      }
  }
}