googleMap.setMapType不起作用

Question

我在我的Android应用程序中遇到了googleMap.setMapType的问题。我选择googleMap.setMapType在我的主菜单中这个功能对GOOGLE地图没有影响，为什么？

这是我的代码：

public class MainActivity extends FragmentActivity {

private GoogleMap googleMap;
private static final LatLng casa = new LatLng(48.411709,10.971354);

@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    if (googleMap == null) {  
        googleMap = ((SupportMapFragment) getSupportFragmentManager()   
                .findFragmentById(R.id.map)).getMap();  

        if (googleMap != null) {  



        googleMap.addMarker(new MarkerOptions().position(casa) 
                    .title("...  CASA ...").snippet("LA MIA CASA.") 
                .draggable(true));

        googleMap.setMyLocationEnabled(true);


        googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(casa, 5));

        googleMap.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null); 






        }

        }





}  



@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
} 


 @Override
 public boolean onOptionsItemSelected(MenuItem item)
 {

     switch (item.getItemId())
     {
     case R.id.mapsat:

            googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);

           return true;






     default:
         return super.onOptionsItemSelected(item);
     }


  }
    }

你有解决方案吗？谢谢!!