title: Pushing arrays in ionic 4
body: <p>I have a Ionic App and I am trying to get latitude and longitude from data api as Json format, for a flight route. The data contains arrays . I want to push arrays into Google maps <code>polylin</code>e to get flight route on map but I get an error when I run the app. </p>
  
  <p>My full code: </p>
  
  <pre class="lang-js prettyprint-override"><code>export class HomePage{
    map: GoogleMap;
    latitude: any;
    longitude: any;
    constructor(
      public toastCtrl: ToastController,
      private platform: Platform,
      private http: HTTP
      ) { }
  
  ngOnInit() {
      // Since ngOnInit() is executed before `deviceready` event,
      // you have to wait the event.
      this.platform.ready();
      this.getmarker();
  
  
    }
  
    getmarker(){
      this.http.get('xxxxxxx/v1/flight.json?flightId=201',{},{})
      .then(data=&gt;{
  
        this.latitude = JSON.parse(data.data).result.response.data.flight.track.latitude
        this.longitude = JSON.parse(data.data).result.response.data.flight.track.longitude
        console.log(this.latitude,this.longitude)
  
        this.loadMap()
      })
    }
  
    loadMap() {
  
  
      let HND_AIR_PORT = this.latitude;
      let SFO_AIR_PORT = this.longitude
  
      let AIR_PORTS = [
        HND_AIR_PORT,
        SFO_AIR_PORT
      ];
  
      this.map = GoogleMaps.create('map_canvas');
  
      let polyline: Polyline = this.map.addPolylineSync({
        points: AIR_PORTS,
        color: '#AA00FF',
        width: 10,
        geodesic: true,
        clickable: true  // clickable = false in default
      });
  
      polyline.on(GoogleMapsEvent.POLYLINE_CLICK).subscribe((params: any) =&gt; {
        let position: LatLng = &lt;LatLng&gt;params[0];
  
        let marker: Marker = this.map.addMarkerSync({
          position: position,
          title: position.toUrlValue(),
          disableAutoPan: true
        });
        marker.showInfoWindow();
      });
    }
  }
  </code></pre>
  
  <p>The error I am getting: </p>
  
  <pre><code>ERROR Error: Uncaught (in promise): TypeError: Cannot use 'in' operator to search for 'getPosition' in undefined
  TypeError: Cannot use 'in' operator to search for 'getPosition' in undefined
      at getLatLng (plugins/cordova-plugin-googlemaps/www/Common.js:544)
      at Array.map (&lt;anonymous&gt;)
      at Object.convertToPositionArray (plugins/cordova-plugin-googlemaps/www/Common.js:575)
      at Map.addPolyline (plugins/cordova-plugin-googlemaps/www/Map.js:1231)
      at vendor.js:76340
      at GoogleMap.push../node_modules/@ionic-native/google-maps/index.js.GoogleMap.addPolylineSync (vendor.js:76352)
      at HomePage.push../src/app/home/home.page.ts.HomePage.loadMap (home-home-module.js:126)
      at home-home-module.js:114
      at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invoke (polyfills.js:2749)
      at Object.onInvoke (vendor.js:51123)
      at resolvePromise (polyfills.js:3189)
      at polyfills.js:3254
      at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (polyfills.js:2781)
      at Object.onInvokeTask (vendor.js:51114)
      at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (polyfills.js:2780)
      at Zone.push../node_modules/zone.js/dist/zone.js.Zone.runTask (polyfills.js:2553)
      at drainMicroTaskQueue (polyfills.js:2959)
  </code></pre>
  
  <p>Any idea?</p>