启用GPS设置后，刷新地图以显示当前位置

Question

我的应用会在当前位置显示标记。 GPS设置警报对话框将显示GPS是否已禁用。启用GPS并返回应用程序后，地图无法刷新。所以我必须强行停止我的应用并再次打开。如何刷新地图活动？

GoogleMap googleMap;

GPSTracker gps;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);
    try {
        ViewMap();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

private void ViewMap() {
    if(googleMap == null) {
        SupportMapFragment supportMapFragment =
                (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.googleMap);
        googleMap = supportMapFragment.getMap();

        gps = new GPSTracker(MainActivity.this);

        if(gps.canGetLocation()) {

            double latitude = gps.getLatitude();
            double longitude = gps.getLongitude();

            LatLng latLng = new LatLng(latitude,longitude);

            TextView locationTv = (TextView) findViewById(R.id.latlongLocation);
            googleMap.addMarker(new MarkerOptions().position(latLng));
            googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
            googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
            locationTv.setText("Latitude:" + latitude + ", Longitude:" + longitude);
        }
        else {
            gps.showSettingsAlert();
        }
    }
}

@Override
protected void onResume() {
    super.onResume();
    ViewMap();
}