Ionic 2 Problem with GoogleMaps

Question

Ionic 2 Problem with GoogleMaps

I try to add Google Maps to my Ionic 2 project, but I get a set of errors:

"Error: exec proxy not found for :: GoogleMaps :: getMap" "Error: exec proxy not found for :: GoogleMaps :: exec"

I copied the sample code from https://ionicframework.com/docs/native/google-maps/

import { Component } from '@angular/core';
import {
 GoogleMaps,
 GoogleMap,
 GoogleMapsEvent,
 LatLng,
 CameraPosition,
 MarkerOptions,
 Marker
} from '@ionic-native/google-maps';

@Component({
  selector: 'page-map',
  templateUrl: 'map.html'
})


export class MapPage {

 constructor(private googleMaps: GoogleMaps) {}

ionViewDidLoad() {
 this.loadMap();
}

loadMap() {

 let element: HTMLElement = document.getElementById('map');

 let map: GoogleMap = this.googleMaps.create(element);

 map.one(GoogleMapsEvent.MAP_READY).then(() => console.log('Map is ready!'));

 let ionic: LatLng = new LatLng(43.0741904,-89.3809802);

 let position: CameraPosition = {
   target: ionic,
   zoom: 18,
   tilt: 30
 };
 map.moveCamera(position);
 let markerOptions: MarkerOptions = {
   position: ionic,
   title: 'Ionic'
 };

  const marker: Marker = map.addMarker(markerOptions)
   .then((marker: Marker) => {
      marker.showInfoWindow();
    });
 }

}