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

Inner class created yet error

In this code, I tried the code challenge on hard mode and then got congratualtions. Now I am completing the tasks and it tells me to create an inner class when its clearly already there.

MainActivity.java
// some methods omitted
public class MainActivity extends Activity {
    Boolean isBound = false;
    Messenger mServiceMessenger;
  Messenger mActivityMessenger=new Messenger(new ActivityHandler(this));
    private int latitude;
  private int longitude;

  class ActivityHandler extends Handler{
  private MainActivity mMainActivity;
   public ActivityHandler(MainActivity mainActivity){
    mMainActivity =mainActivity;
    }

  @Override
  public void handleMessage(Message msg){
  latitude=msg.arg1;
  longitude=msg.arg2;
    mMainActivity.setCoordinates(latitude,longitude);
  }
  }


    ServiceConnection mServiceConnection = new ServiceConnection() {
      @Override  
      public void onServiceConnected(ComponentName name, IBinder binder) {
        isBound = true;
        mServiceMessenger=new Messenger(binder);
        Message message=Message.obtain();
        message.replyTo=mActivityMessenger;
        try{
        mServiceMessenger.send(message);
        }
        catch(Exception e){
        e.printStackTrace();
      }
      }

      @Override
      public void onServiceDisconnected(ComponentName name) {
        isBound = false;
      }
    };
}
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();
        mLongitude = getLongitude();
        Message message=Message.obtain();
        message.arg1=mLatitude;
        message.arg2=mLongitude;
        try{
        msg.replyTo.send(message);

        }
        catch(Exception e){
        e.printStackTrace();
        }
      }
    }
}
Difficulty.java
  public class Difficulty {
    public static Boolean HARDMODE = false;    
  }

1 Answer

So managed to find a solution. It seems that the constructor of the inner class in main activity was an issue. Also added private keyword to the declaration and that seemed to solve the problem. Apparently the inner class in MainActivity should be structured similar to that in GeolocationService, only then will it work