How to use the @ionic-native/google-maps.GoogleMapsEvent.CAMERA_MOVE_END function in @ionic-native/google-maps

this.mapElement = document.getElementById('map');
    this.map = this.googleMaps.create(this.mapElement, mapOptions);

    this.map.on(GoogleMapsEvent.MAP_READY).subscribe(() => {

      this.map.setMyLocationEnabled(true);
      this.locateMe();

    });

    this.map.on(GoogleMapsEvent.CAMERA_MOVE_START).subscribe(() => {

      this.toggleTrans(true);
    });

    this.map.on(GoogleMapsEvent.CAMERA_MOVE_END).subscribe(() => {

      this.toggleTrans(false);
    });
  }