从队列更新活动的最佳方法

我有一个LinkedBlockingQueue在我的“生产者-调解者-消费者”模型中的调解者中。 Producer 首先更新将 Mediator 添加到 ActivityQueue 中。接下来，消费者/活动在队列中等待/侦听并获取下一个项目。

我想要一个活动来查看队列大小已更改并获取下一个项目。调解员无法了解活动只有活动才能看到中介者。那么我该如何创建我想要的这个监听器机制呢？

这是我的中介类，它保存队列，活动将以某种方式查看队列并获取通知是否需要更新。进入队列的数据有时可能是不稳定且随机的，因此轮询机制将不起作用。

public class MediatorData {

    /** Queue for the Activity */
    LinkedBlockingQueue <byte[]> queueConsumer = new LinkedBlockingQueue <byte[]>();

    /**
     * Add data to a queue(s) for consumption
     */
    public void put(byte[] data) throws InterruptedException {
        queueConsumer.add(data);
    }

    /**
     * Return data from the queue for the Feature calculations
     */
    public byte[] getFeatureData() throws InterruptedException {
        return queueConsumer.poll(100, TimeUnit.MILLISECONDS);
    }

}

我的活动类的示例，它是一个图形类，因此队列侦听器必须高效且快速。

public class DisplayGraph extends Activity {

    // populated from Application Class where its created
    pirvate MediatorData md;

    public void onCreate(Bundle savedInstanceState) {
        md = getMediator();  // This comes from the custom Application class

        ... some type of listener to queue 
    }

    private void getQueueData() {
        byte[] tv = md.queueConsumer.poll();
        // can't update textview  get exception CalledFromWrongThreadException
        ((TextView) DisplayGraph.this.findViewById(R.id.tv)).setText("TV " + tv[0]);
    }
}

怎么样使用Observer http://developer.android.com/reference/java/util/Observer.html and 可观察的 http://developer.android.com/reference/java/util/Observable.html?

可能是这样的：

public class MediatorData extends Observable {

    /** Queue for the Activity */
    LinkedBlockingQueue <byte[]> queueConsumer = new LinkedBlockingQueue <byte[]>();

    /**
     * Add data to a queue(s) for consumption
     */
    public void put(byte[] data) throws InterruptedException {
        queueConsumer.add(data);
        setChanged();
        notifyObservers();
    }

    /**
     * Return data from the queue for the Feature calculations
     */
    public byte[] getFeatureData() throws InterruptedException {
        return queueConsumer.poll(100, TimeUnit.MILLISECONDS);
    }
}

和这个：

public class DisplayGraph extends Activity implements Observer {

    // populated from Application Class where its created
    private MediatorData md;

    public void onCreate(Bundle savedInstanceState) {
        md = getMediator();  // This comes from the custom Application class
        md.addObserver(this);
    }

    private void getQueueData() {
        byte[] tv = md.queueConsumer.poll();
        // can't update textview  get exception CalledFromWrongThreadException
        ((TextView) DisplayGraph.this.findViewById(R.id.tv)).setText("TV " + tv[0]);
    }

    public void update(Observable arg0, Object arg1) {
        getQueueData();
    }
}