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Android Threads and Services But Wait There's More! Messengers and Handlers: Activity

Handle the Message in GeolocationService, and use the 'replyTo' property to send a new Message back to MainActivity with

setCoordinates not accessible

// some methods omitted

public class MainActivity extends Activity {
    Boolean isBound = false;
  int latitude;
  int longitude;
    Messenger mServiceMessenger;
      public  Messenger mMainActivityMessenger = new Messenger(new LocHandler());

    ServiceConnection mServiceConnection = new ServiceConnection() {
      public void onServiceConnected(ComponentName name, IBinder binder) {

        isBound = true;
        mServiceMessenger = new Messenger(binder);
          if (mServiceMessenger != null) {
                Message msg = Message.obtain();
                msg.replyTo = mMainActivityMessenger;


    public void setCoordinates(int lat, int longi) {
      public void onServiceDisconnected(ComponentName name) {
        isBound = false;
class LocHandler extends Handler {
      public void handleMessage(Message msg) {
     // mServiceMessenger =   new Messenger(new LocHandler());
          setCoordinates(msg.arg1, msg.arg2);

// some methods omitted
public class GeolocationService extends Service {
    int mLatitude;
    int mLongitude;
    public Messenger mMessenger = new Messenger(new LocationHandler());

    public IBinder onBind(Intent intent) {
      return mMessenger.getBinder();

   class LocationHandler extends Handler {
    // public MainActivity main;
   //  public LocHandler hand = new LocHandler();

      public void handleMessage(Message msg) {

       mLatitude = getLatitude(); 
        mLongitude = getLongitude();
        Message message = Message.obtain();
        message.arg1 = mLatitude; 
        message.arg2 = mLongitude;
       // message.replyTo = mMessenger;
       // message.replyTo.send(msg);

  //setCoordinates(message.arg1, message.arg2);
          //setCoordinates(mLatitude, mLongitude);

  public class Difficulty {
    public static Boolean HARDMODE = false;