如何在Android中绘制Google地图中的自由手多边形？

GoogleMap googleMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
googleMap.setMyLocationEnabled(true);

PolygonOptions polygonOptions = new PolygonOptions();
polygonOptions.strokeColor(Color.RED);
polygonOptions.strokeWidth(5);
polygonOptions.fillColor(Color.BLUE);

googleMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
    @Override
    public void onMapClick(LatLng latLng) {
        polygonOptions.add(latLng);
        googleMap.addPolygon(polygonOptions);
    }
});

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<meta-data
    android:name="com.google.android.geo.API_KEY"
    android:value="YOUR_API_KEY" />