Android Google Map : Marker from Current Location (LocationChanged)

package com.myapp;

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;

public class MainActivity extends FragmentActivity implements LocationListener {

	protected LocationManager locationManager;
	protected LocationListener locationListener;
	
	// Google Map
	private GoogleMap googleMap;	

	// Latitude & Longitude
	private Double Latitude  = 0.00;
	private Double Longitude  = 0.00;

	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		//*** Location 
		locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
		locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
		
        //*** Display Google Map
        googleMap = ((SupportMapFragment)getSupportFragmentManager()
                .findFragmentById(R.id.googleMap)).getMap(); 	
	}

	@Override
	public void onLocationChanged(Location location) {
		
		if (location == null) { return; }
		
		//** Get Latitude & Longitude
		Latitude = location.getLatitude();
		Longitude= location.getLongitude();

		googleMap.clear();
		
        //*** Focus & Zoom
        LatLng coordinate = new LatLng(Latitude, Longitude);
        googleMap.setMapType(com.google.android.gms.maps.GoogleMap.MAP_TYPE_HYBRID);
        googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 17));
        
        //*** Marker
        MarkerOptions marker = new MarkerOptions()
        		.position(new LatLng(Latitude, Longitude)).title("Your current location");
        marker.icon(BitmapDescriptorFactory.fromResource(R.drawable.marker));
        googleMap.addMarker(marker);
	}

	@Override
	public void onProviderDisabled(String provider) {
		// Log.d("Latitude","disable");
	}

	@Override
	public void onProviderEnabled(String provider) {
		// Log.d("Latitude","enable");
	}

	@Override
	public void onStatusChanged(String provider, int status, Bundle extras) {
		// Log.d("Latitude","status");
	}

}