Locations

MainActivity.java

public class MainActivity extends Activity implements
        GooglePlayServicesClient.ConnectionCallbacks,
        GooglePlayServicesClient.OnConnectionFailedListener,
        LocationListener,
        LocationClient.OnAddGeofencesResultListener {
    private LocationClient mLocationClient;

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

        mLocationClient = new LocationClient(this, this, this);
    }

    @Override
    protected void onStart() {
        super.onStart();

        mLocationClient.connect();
    }

    @Override
    public void onConnected(Bundle dataBundle) {
        // this callback will be invoked when the client is connected
        // from now on, you can fetch current location and listen to location updates

        // fetch the current location
        // note that this method might return null in a very rare case (i.e. location is not available)
        Location location = mLocationClient.getLastLocation();

        // start listening to location updates
        // this is suitable for foreground listening, with the onLocationChanged() invoked for location updates
        LocationRequest locationRequest = LocationRequest.create()
                .setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)
                .setFastestInterval(5000L)
                .setInterval(10000L)
                .setSmallestDisplacement(75.0F);
        mLocationClient.requestLocationUpdates(locationRequest, this);

        // this is suitable for background location tracking
        // your MyLocationHandler service will still be triggered even if your app is killed by the system
        PendingIntent pendingIntent = PendingIntent.getService(this, 0,
                new Intent(this, MyLocationHandler.class),
                PendingIntent.FLAG_UPDATE_CURRENT);
        mLocationClient.requestLocationUpdates(locationRequest, pendingIntent);

        // adds geofencing
        ArrayList<Geofence> geofences = new ArrayList<Geofence>();
        geofences.add(new Geofence.Builder()
                .setRequestId("unique-geofence-id")
                .setCircularRegion(60.1708, 24.9375, 1000)
                .setTransitionTypes(Geofence.GEOFENCE_TRANSITION_ENTER
                        | Geofence.GEOFENCE_TRANSITION_DWELL
                        | Geofence.GEOFENCE_TRANSITION_EXIT)
                .setLoiteringDelay(30000) // GEOFENCE_TRANSITION_DWELL will be notified 30 seconds after the device enters the area
                .build());
        PendingIntent pendingIntent2 = PendingIntent.getService(this, 0,
                new Intent(this, MyGeofenceHandler.class),
                PendingIntent.FLAG_UPDATE_CURRENT);
        mLocationClient.addGeofences(geofences, pendingIntent2, this);
    }

    @Override
    public void onDisconnected() {
        // this callback will be invoked when the client is disconnected
        // it might happen e.g. when the location service crashes
        // you can't access until it's connected again
    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        // this callback will be invoked when the connection attempt fails

        if (connectionResult.hasResolution()) {
            // Google Play services can fix the issue
            try {
                connectionResult.startResolutionForResult(this, 0);
            } catch (IntentSender.SendIntentException e) {
                // it happens if the resolution intent has been canceled,
                // or is no longer able to execute the request.
            }
        } else {
            // Google Play services has no idea how to fix the issue
            // it rarely happens for the location service
        }
    }

    @Override
    public void onLocationChanged(Location location) {
        // this callback is invoked when location updates
    }

    @Override
    public void onAddGeofencesResult (int statusCode, String[] geofenceRequestIds) {
        // this callback is invoked when geofences are added, either succeed or fail
    }

    @Override
    protected void onStop() {
        if (mLocationClient.isConnected())
            mLocationClient.removeLocationUpdates(this);
        mLocationClient.disconnect();

        super.onStop();
    }
}