lazyload1.service.ts

export class LazyLoadService {
  delayMsec = 0;

  // announce order to [lazyLoad] directives
  private order$ = new Subject<string>();
  announcedOrder = this.order$.asObservable();
  announceOrder(name: string) {
    this.order$.next(name);
  }

  registerAfter(msec: number) {
    if (msec > 0) {
      this.delayMsec = msec;
      setTimeout(_ => this.announceOrder('register'), msec);
    }
  }