title: How to change MapType with GoogleMapController?
body: <p>I want to change MapType with GoogleMapController.
  I use a floatingActionButtom for change this.
  GoolgeMapOptions is removed from GoogleMap widget and I can not use this property.
  Now I don't know what code to use instead.
  I want to change Maptype (from normal to satellite) by onMapType function but I can not use updateMapOptions and GoolgeMapOptions in new version GoogleMap.</p>
  
  <pre><code>class MapScreen extends StatefulWidget{
    @override
    State&lt;StatefulWidget&gt; createState() =&gt; new MapScreenState();
  }
  
  class MapScreenState extends State&lt;MapScreen&gt;{
    GoogleMapController mapController;
    MapType currentMaptype=MapType.normal;
    final myGoogleMap=GlobalKey();
  
    void _onMapController(GoogleMapController controller){
      mapController=controller;
    }
    void _onMaptype(){
      if(currentMaptype==MapType.normal){
       mapController.updateMapOptions(
          GoogleMapOptions(mapType: MapType.satellite);
        currentMaptype=MapType.satellite;
      }
      else{
        mapController.updateMapOptions(
          GoogleMapOptions(mapType: MapType.normal);
        currentMaptype=MapType.normal;
      }
    }
    @override
    Widget build(BuildContext context) {
      // TODO: implement build
      return   new Scaffold(
        body: new Stack(
          alignment: Alignment.bottomCenter,
          children: &lt;Widget&gt;[
            new GoogleMap(
              initialCameraPosition:CameraPosition(
              target: LatLng(85.254, 74.542)) ,
              onMapCreated:_onMapController,
              mapType: currentMaptype,
            ),
            new Align(
              alignment: Alignment.bottomLeft,
              child: new Padding(
                padding: EdgeInsets.only(bottom: 25, left: 8) ,
                child: new Column(
                  mainAxisAlignment: MainAxisAlignment.end,
                  children: &lt;Widget&gt;[
                    new FloatingActionButton(
                      onPressed: _onMaptype,
                      backgroundColor: Colors.green,
                      child: new Icon(Icons.map, color: Colors.white,size: 30),
                    ),
                  ],
                ),
              ),
            )
          ],
        ),
      );
    }
    }
  </code></pre>