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

Posted by Glen Chiridza
Glen Chiridza
8,441 Points

Send a Message to GeolocationService from MainActivity. Include MainActivity's Messenger in the Message as the 'replyTo'

bummer: make sure you extending handler class

MainActivity.java 
// some methods omitted
public class MainActivity extends Activity {
    Boolean isBound = false;
    Messenger mServiceMessenger;
      public  Messenger mMainActivityMessenger = new Messenger(new LocHandler());

    ServiceConnection mServiceConnection = new ServiceConnection() {
      @Override  
      public void onServiceConnected(ComponentName name, IBinder binder) {
        mServiceMessenger = new Messenger(binder);
        if (mServiceMessenger != null) {
                Message msg = Message.obtain();
          msg.arg1=2;
                msg.replyTo = mMainActivityMessenger;
                mServiceMessenger.send(msg);
        }

        isBound = true;
      }

      @Override
      public void onServiceDisconnected(ComponentName name) {
        isBound = false;
      }
    };
class LocHandler extends Handler {
      @Override
      public void handleMessage(Message msg) {
        mServiceMessenger =   new Messenger(new LocHandler());
      // msg.replyTo = mServiceMessenger.mMainActivityMessenger.
       /* msg.arg1= getLatitude();
                 msg.arg2 = getLongitude();

        msg.replyTo.send(msg);*/
      if(msg.arg1==0){
        Message message = Message.obtain();
        message.arg1=0;
        msg.replyTo.send(message);
      }
        else if(msg.arg1==1){
          Message message = Message.obtain();
        message.arg1=1;
          msg.replyTo.send(message);
        }


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

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

   class LocationHandler extends Handler {
      @Override
      public void handleMessage(Message msg) {


         mLatitude = getLatitude();
        Message message = Message.obtain();
        message.arg1= mLatitude ;
        message.replyTo =mMessenger;
          mLongitude = getLongitude();

          //setCoordinates(mLatitude, mLongitude);

      }
    }
}
Difficulty.java 
  public class Difficulty {
    public static Boolean HARDMODE = false;    
  }