Para saber si una solicitud se ha completado, hagoif (httpEvent instanceof HttpResponse). Del mismo modo, cómo saber si una solicitud se cancela enHttpInterceptor? Abajo está miintercept función.

intercept(httpRequest: HttpRequest<any>, httpHandler: HttpHandler): Observable<HttpEvent<any>> {
    this.requestsPending++;

    if (this.typeAheads.includes(httpRequest.url.split('/').pop()))
      this.slimLoadingBarService.start();
    else
      this.flsLoaderService.start();

    return httpHandler.handle(httpRequest)
      .do((httpEvent: HttpEvent<any>) => {
        if (httpEvent instanceof HttpResponse) {
          // decrementing counter on each request return
          this.requestsPending--;

          if (this.typeAheads.includes(httpEvent.url.split('/').pop())) {
            if (this.requestsPending === 0)
              this.slimLoadingBarService.complete();
          }
          else {
            if (this.requestsPending === 0)
              this.flsLoaderService.stop();
          }
        }
      }, () => {
        this.slimLoadingBarService.complete();

        // reset counter on error
        this.requestsPending = 0;
        this.flsLoaderService.stop();
      });
  }