BehaviorSubject.next不会使用异步管道更新视图

我尝试使用Google Places Js API检索Google Places，并使用BehaviorSubject.next通过异步管道更新我的Angular视图，但视图未更新。

实际上，有时15秒后会发生。有时我必须单击某处。但是我确定的是，当我从Google服务器获得结果时，它不会更新...（我将其记录下来）。

这是我的搜索功能：

    import { AfterViewInit, Component, ViewChild, ElementRef } from '@angular/core';
import { LoadingController, NavParams, ViewController, Platform } from 'ionic-angular';
import {BehaviorSubject} from 'rxjs/BehaviorSubject';
declare var google;

@Component({
  selector: 'page-new-location-modal',
  templateUrl: 'new-location-modal.html'
})
export class NewLocationModalPage {

  @ViewChild('map') map: ElementRef;

  // ngModel for segment
  googleSearchType: string;

  // Sport retrieved from previous page (newEventForm)
  sport = '';

  // Props used for suggestion func
  mapElem: ElementRef;
  googleService: any;
  places$:BehaviorSubject= new BehaviorSubject([]);


  constructor(
    public platform: Platform,
    public viewCtrl: ViewController,
    public loadingCtrl: LoadingController,
    public params: NavParams
  ) {
    console.log('NewLocationModal#constructor');

    // Sport must be retrieved from params
    this.sport = params.get('sport');
  }

  ngAfterViewInit(): void {
    // Init Google service
    this.mapElem = this.map.nativeElement;
    this.googleService = new google.maps.places.PlacesService(this.mapElem);

    // Select Suggestion segment
    this.googleSearchType = 'suggestion';
    // Trigger searchSuggestionsForSport()
    this.searchSuggestionsForSport(this.sport);

  }

  onSegmentChange(segment): void {
    console.log('NewLocationModal#onSegmentChange - Selected segment ', segment.value);

    if (segment.value === 'suggestion') {
      this.searchSuggestionsForSport(this.sport);
    }
  }

  searchSuggestionsForSport(sport: string): void {
    console.log('NewLocationModal#searchSuggestionsForSport - Sport ', sport);

    let location = new google.maps.LatLng(48.862725,2.287592000000018);
    let request = {
      location: location,
      keyword: sport,
      rankBy: google.maps.places.RankBy.DISTANCE
    };

    // Google Places Service


    // NearBy Search
    this.googleService.nearbySearch(request, (places) => {
      // First set of information sent to the async pipe in view
      this.places$.next(places);

      console.log(places);
    });
  }

  dismiss() {
    this.viewCtrl.dismiss();
  }
}

          
            
              
                {{place.name}} - {{place.rating}}
              
              

                {{place.vicinity}}
              
            
          
        

 constructor(
    public platform: Platform,
    public viewCtrl: ViewController,
    public loadingCtrl: LoadingController,
    public params: NavParams,
    private zone:NgZone,
  ) {

...

    // NearBy Search
    this.googleService.nearbySearch(request, (places) => {
      // First set of information sent to the async pipe in view
      this.zone.run(() => this.places$.next(places));
      console.log(places);
    });