Android Maps onLocationChanged（）从不调用片段

Question

您好我正在使用

显示用户位置地图

        googleMap.setMyLocationEnabled(true);

请求许可后。

多数工作，但为什么永远不会调用onLocationChanged方法？可能我应该实现LocationListener，但我真的想知道在处理片段时该怎么做。

public class tab2_fragment extends Fragment {
    private static final String TAG = "Tab2Fragment";

    MapView mMapView;
    private GoogleMap googleMap;
    public static final int REQUEST_LOCATION = 1;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.tab2_fragment, container, false);

        mMapView = (MapView) rootView.findViewById(R.id.mapView);
        mMapView.onCreate(savedInstanceState);

        mMapView.onResume(); // needed to get the map to display immediately
       // googleMap.setMapStyle(
               // MapStyleOptions.loadRawResourceStyle(
                        //this, R.raw.mapstyle));
        try {
            MapsInitializer.initialize(getActivity().getApplicationContext());
        } catch (Exception e) {
            e.printStackTrace();
        }

        mMapView.getMapAsync(new OnMapReadyCallback() {
            @Override
            public void onMapReady(GoogleMap mMap) {
                googleMap = mMap;


                if (ActivityCompat.checkSelfPermission(getContext(),
                        android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
                        ActivityCompat.checkSelfPermission(getContext(),
                                android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(getActivity(),
                            new String[]{android.Manifest.permission.ACCESS_COARSE_LOCATION,
                                    android.Manifest.permission.ACCESS_FINE_LOCATION},
                            REQUEST_LOCATION);
                } else {
                    Log.e("DB", "PERMISSION GRANTED");
                }
                googleMap.setMyLocationEnabled(true);

            }

            public void onLocationChanged(Location location){

                LatLng myLocation = new LatLng(location.getLatitude(), location.getLongitude());
                googleMap.addMarker(new MarkerOptions()
                        .position(myLocation)
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED))
                        .title("My Location"));
                googleMap.moveCamera(CameraUpdateFactory.newLatLng(myLocation));
                Log.d("location", "Latitude:" + location.getLatitude() + "\n" + "Longitude:" + location.getLongitude());

            }
        });

        return rootView;
    }


}