import { ApplicationRef , Component , isDevMode } from '@angular/core' ; import { debounceTime , distinctUntilChanged } from 'rxjs/operators' ; @ Component ( { selector : 'app-root' , template : `
    <h1>AngularFire kitchen sink (<a href="https://github.com/angular/angularfire/tree/master/samples/modular"><code>samples/modular</code></a>)</h1>
    <router-outlet></router-outlet>
  ` , styles : [ ] } ) export class AppComponent { title = 'sample' ; constructor ( appRef ) { if ( isDevMode ( ) ) { appRef . isStable . pipe ( debounceTime ( 200 ) , distinctUntilChanged ( ) ) . subscribe ( it => { console . log ( 'isStable' , it ) ; } ) ; } } }