how to use googlemap v2 over fragment

how to use googlemap v2 over fragment

class MyFragment extends Fragment
{
      SupportMapFragment myMapFragment;
    GoogleMap myMap;
    View convertView;
    FragmentManager fm;
    public View onCreateView(LayoutInflater inflater, ViewGroup container,  Bundle savedInstanceState) {

    convertView=inflater.inflate(R.layout.mymap,null);
    fm=getChildFragmentManager();
        myMapFragment=(SupportMapFragment) fm.findFragmentById(R.id.myMapId);


        // here instead of using getMap(), we are using getMapAsync() which returns a callback and shows map only when it gets ready.
        //it automatically checks for null pointer or older play services version, getMap() is deprecated as mentioned in google docs.


        myMapFragment.getMapAsync(new OnMapReadyCallback() {

            @Override
            public void onMapReady(GoogleMap googlemap) {
                // TODO Auto-generated method stub
                myMap=googlemap;
                startMap();
            }
        });


    return convertView;
    }

}

https://stackoverflow.com/questions/25653898/google-maps-fragment-returning-null-inside-a-fragment