我需要根据经纬度在地图中显示特定位置,并在该特定位置显示标记。但是,我已经显示了整个地图,但没有得到具体的位置。
public class MapActivity extends FragmentActivity {
GoogleMap googleMap;
MarkerOptions markerOptions;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
       setContentView(R.layout.map);
    Intent intent = getIntent();
    String title = intent.getStringExtra("title");
    String lat = intent.getStringExtra("lat");
    String lon = intent.getStringExtra("long");
    double Lon = Double.parseDouble(lon);
    double Lat = Double.parseDouble(lat);
    SupportMapFragment supportMapFragment = (SupportMapFragment)
    getSupportFragmentManager().findFragmentById(R.id.map);
    googleMap = supportMapFragment.getMap();
    googleMap.addMarker(new MarkerOptions()
            .position(new LatLng(Lat, Lon))
            .title(title));
      } }