android - 如何在位置周围添加半径？

Question

我怎样才能在这里添加半径..或动态...？？

 {
                GPSLongitude = location.getLongitude();
                GPSLatitude = location.getLatitude();
                Log.i("GPS","Lat: "+GPSLatitude+" Long "+ GPSLongitude);
                Toast.makeText(getApplicationContext(), "Location is "+GPSLatitude+" Long "+ GPSLongitude, Toast.LENGTH_LONG).show();
                googleMap.moveCamera( CameraUpdateFactory.newLatLngZoom(new LatLng(GPSLatitude,GPSLongitude) , 16.0f) );
                }