Hi guys, Any idea what might be wrong here please?

import android.os.AsyncTask;
import android.os.Bundle;

public class CustomActivity extends Activity {

    public String mStatus;

  @Override
    protected void onPostExecute(String result) {

    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_custom);
        CustomAsyncTask task = new CustomAsyncTask();
        task.execute();
    }

    protected void updateStatusLabel() {
        super.updateStatusLabel();
    }

    protected class CustomAsyncTask extends AsyncTask<Object, Void, String> {   
        @Override
        protected String doInBackground(Object... params) {
            // Imagine this is some code to do some work
            return "Done!";
        }


    }
}