A Handler allows you to send and process Message and Runnable objects associated with a thread's MessageQueue.

private class DataSentRunnable implements Runnable {
  private RPStream stream;
  public DataSentRunnable(RPStream stream) {
	 this.stream = stream;
  }

  public void run() {
    parent.onDataSent(stream);
  }
}

Handler handle = new Handler();
this.handler.post(cr);