能否在IntentService无限期地运行？ [英] Can an IntentService run indefinitely?

问题描述

根据我的理解，一个IntentService将获得当它的当前请求完成后停止。

Based on my understanding, an IntentService will get stopped when its current request is done.

请考虑以下的情况下，我会触发一个请求到IntentSerivce为每100ms和处理时间将是90毫秒的要求。

Consider the below scenario, i will be triggering a request to the IntentSerivce for every 100ms and the processing time will be 90 ms for that request.

因此​​，对于每一个我的要求 - startSerivce电话，服务将被调用后90毫秒（一旦处理完成），该IntentServicee中的onDestroy将被调用

So for every my request - startSerivce call, service will get invoked and after 90ms (once the processing is done), onDestroy of the IntentServicee will get invoked.

我想有这个IntentServicee运行，直到我说停止。这可能吗？

I would like to have this IntentServicee running till i say stop. Is that possible?

假设我打算做低于我的服务

assume that i am going to do the below in my service

1. 请配置
2. 发送一些要求
3. 在等待回应
4. 在读取响应
5. 广播来的活动，调用

第1步是适用于所有我的要求，所以我想我可以做他们当服务已启动最初一次，根据请求的HandleIntent然后做3-6。

Steps 1 is common for all my requests, so i thought i can do them when service is started initially once and then do 3-6 in HandleIntent based on the requests.

推荐答案

在 IntentService 实际上是pretty的小班它包装一个处理程序，问题在于一个Intent已处理后，它会调用 stopSelf（）。

The IntentService is actually a pretty small class which wraps a Handler, the problem being that after an Intent has been handled it calls stopSelf().

删除了一行给你一个IntentService需要被明确停止：

Removing that single line gives you an IntentService which needs to be explicitly stopped:

public abstract class NonStopIntentService extends Service {

    private String mName;
    private volatile Looper mServiceLooper;
    private volatile ServiceHandler mServiceHandler;

    public NonStopIntentService(String name) {
        super();
        mName = name;
    }

    private final class ServiceHandler extends Handler {
        public ServiceHandler(Looper looper) {
            super(looper);
        }

        @Override
        public void handleMessage(Message msg) {
            onHandleIntent((Intent)msg.obj);
            // stopSelf(msg.arg1); <-- Removed
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        HandlerThread thread = new HandlerThread("IntentService[" + mName + "]");
        thread.start();

        mServiceLooper = thread.getLooper();
        mServiceHandler = new ServiceHandler(mServiceLooper);
    }

    @Override
    public void onStart(Intent intent, int startId) {
        Message msg = mServiceHandler.obtainMessage();
        msg.arg1 = startId;
        msg.obj = intent;
        mServiceHandler.sendMessage(msg);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        onStart(intent, startId);
        return START_STICKY;
    }    

    @Override
    public void onDestroy() {
        mServiceLooper.quit();
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }

    /**
     * This method is invoked on the worker thread with a request to process.
     * Only one Intent is processed at a time, but the processing happens on a
     * worker thread that runs independently from other application logic.
     * So, if this code takes a long time, it will hold up other requests to
     * the same IntentService, but it will not hold up anything else.
     *
     * @param intent The value passed to {@link
     *               android.content.Context#startService(Intent)}.
     */
    protected abstract void onHandleIntent(Intent intent);  

}

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