google 地图地点自动完成 addEventListener 不起作用

Question

我一直在尝试添加 google maps places auto complete in ionic 2 project 以更新用户 location.However，addEventListener 似乎不起作用并且没有控制台错误任何人都可以告诉我哪里错了？

 ngAfterViewInit() {
   let input = < HTMLInputElement > document.getElementById("auto");
   console.log('input', input);
   let options = {
     componentRestrictions: {
       country: 'IN',
       types: ['(regions)']
     }
   }
   let autoComplete = new google.maps.places.Autocomplete(input, options);
   console.log('auto', autoComplete);
   google.maps.event.addListener(autoComplete, 'place_changed', function() {
     this.location.loc = autoComplete.getPlace();
     console.log('place_changed', this.location.loc);
   });
 }

<ion-label stacked>Search Location</ion-label>
<input type="text" id="auto" placeholder="Enter Search Location" [(ngModel)]="location.loc" />

index.html

<script src="https://maps.googleapis.com/maps/api/js?key=xxxxxxxxxxxxxx&libraries=places"></script>

Answer 1

尝试使用以下组件检查 autoComplete 上的 place_changed 事件：

import {Component, ViewChild, ChangeDetectorRef} from '@angular/core';

@Component({
  selector: 'my-app',
  template: `
    <div>      
      <input #auto />
      {{ location?.formatted_address | json}}
    </div>
  `,
})
export class App {
  @ViewChild('auto') auto:any;

  location: any;

  constructor(private ref: ChangeDetectorRef) {
  }

  ngAfterViewInit(){
    let options = {
      componentRestrictions: {
        country: 'IN'
      }
    };
    let autoComplete = new google.maps.places.Autocomplete(this.auto.nativeElement, options);

    console.log('auto', autoComplete);

    autoComplete.addListener('place_changed', () => {
      this.location = autoComplete.getPlace();
      console.log('place_changed', this.location);
      this.ref.detectChanges();
    });
  }
}

由于 place_changed 是在 angular js 之外触发的，我们需要手动触发 angular 使用 ChangeDetectorRef 的变化检测。

Answer 2

您可以使用箭头函数来保留 this 和 ChangeDetectionRef 来检测更改，因为 google 地图事件在 angular 区域外触发：

constructor(private cd: ChangeDetectorRef) { }

google.maps.event.addListener(autoComplete, 'place_changed', () => { // arrow function
  this.location.loc = autoComplete.getPlace();
  this.cd.detectChanges(); // detect changes
  console.log('place_changed', this.location.loc);
});

autoComplete.getPlace(); returns对象，所以可以得到如下地址：

var place =  autoComplete.getPlace();
this.location.loc = place.formatted_address;

Plunker Example

google 地图地点自动完成 addEventListener 不起作用

google maps places autocomplete addEventListener doesn't work

ionic2

google-maps-autocomplete

angular