Android的服务线程使Web请求被阻塞UI [英] Android service thread making web request is blocking UI

问题描述

首先，我要解释一下目前的情况。
我在2服务2不同的线程（从USB端口的服务阅读和Web请求服务）。我开始他们的onCreate我的活动一样的：

First I will explain the current situation. I've 2 different threads in 2 services(read from usb port service and make web requests service). I'm starting them in onCreate of my activity like:

serialServiceIntent = new Intent(NDKSerialActivity.this, SerialService.class);
startService(serialServiceIntent);
webServiceIntent = new Intent(NDKSerialActivity.this, RecordWebService.class);
startService(webServiceIntent);

有什么错串行服务，但在RecordWebService当我提出我的GUI停止，直到来响应请求。

There is nothing wrong with serial service but in RecordWebService when I make a request my gui stops until response comes.

在code是这样的：

public class RecordWebService extends Service
{
public static final String SERVER_ADDRESS = "http://192.168.1.100:8080/MobilHM/rest";
private static final String TAG = RecordWebService.class.getSimpleName();
private RecordWebThread recordWebThread;

@Override
public void onStart(Intent intent, int startId)
{
    super.onStart(intent, startId);
    recordWebThread = new RecordWebThread(true);
    recordWebThread.start();
}

@Override
public void onDestroy()
{
    super.onDestroy();
    Log.i(TAG, "RecordWebService Destroyed");
}

@Override
public IBinder onBind(Intent intent)
{
    return null;
}
}

和

public class RecordWebThread extends Thread
{
private static final String TAG = RecordWebThread.class.getSimpleName();
public boolean always;


public RecordWebThread(boolean always)
{
    this.always = always;
}

@Override
public void run()
{
    PatientRecord patientRecord = new PatientRecord();
    while (always)
    {
        RestClient restClient = new RestClient(RecordWebService.SERVER_ADDRESS + "/hello");
        try
        {
            restClient.execute(RequestMethod.GET);
        }
        catch (Exception e1)
        {
            Log.e(TAG, "", e1);
        }
        Log.i(TAG, "Server Response Code:->" + restClient.getResponseCode());
        Log.i(TAG, "Server Response:->" + restClient.getResponse());
        try
        {
            sleep(4 * 1000);
        }
        catch (InterruptedException e)
        {
            Log.e(TAG, "Web service interrupted", e);
        }
    }
}
}

我也一直在努力，除去睡觉的一部分，使线程与定时器和计时器任务运行一样：

Also I've tried to remove sleep part and make the thread to run with timer and timer task like:

public void sendRecord()
{
    scanTask = new TimerTask()
    {
        public void run()
        {
            handler.post(new Runnable()
            {
                public void run()
                {
                    RestClient restClient = new RestClient(RecordWebService.SERVER_ADDRESS + "/hello");
                    try
                    {
                        restClient.execute(RequestMethod.GET);
                    }
                    catch (Exception e1)
                    {
                        Log.e(TAG, "", e1);
                    }
                    Log.i(TAG, "Server Response Code:->" + restClient.getResponseCode());
                    Log.i(TAG, "Server Response:->" + restClient.getResponse());
                }
            });
        }
    };
    t.schedule(scanTask, 1000, 4000);
}

但没有运气，我的GUI，当谈到restClient.execute挂起。

but no luck, my gui hangs when it comes to restClient.execute .

您可以找到RestClient.java @ http://www.giantflyingsaucer.com/blog/ p = 1462

You can find RestClient.java @ http://www.giantflyingsaucer.com/blog/?p=1462

我怎样才能让我的请求，不会阻止我的GUI线程？

How can I make my requests not block my gui thread?

编辑：

public void sendRecord()
{
    scanTask = new TimerTask()
    {
        public void run()
        {
            RestClient restClient = new RestClient(RecordWebService.SERVER_ADDRESS + "/hello");
            try
            {
                restClient.execute(RequestMethod.GET);
            }
            catch (Exception e1)
            {
                Log.e(TAG, "", e1);
            }
            Log.i(TAG, "Server Response Code:->" + restClient.getResponseCode());
            Log.i(TAG, "Server Response:->" + restClient.getResponse());
        }
    };
    t.schedule(scanTask, 1000, 4000);
}

如果没有处理，我把这个在我的活动的onCreate但仍UI挂。

Without handler, I call this in onCreate of my activity but still ui hanging.

推荐答案

或者你可以使用一个IntentService它将为您处理线程的问题。

Or you can use an IntentService which will handle the thread issues for you.

这是一个示例类：

public class MyService extends IntentService {

    public MyService() {
        super("MyService");
    }

    public MyService(String name) {
        super(name);        
    }

    @Override
    protected void onHandleIntent(Intent arg0) {

                //Do what you want
        }
}

然后你只需拨打：

Then you just call:

Intent intent = new Intent(getApplicationContext(),MyService.class);
startService(intent);

编辑：

要重复同样的事情，每4秒，你应该做这样的事情：

To repeat the same thing every 4 seconds you should do something like this:

 PendingIntent serviceIntent= PendingIntent.getService(context,
                0, new Intent(context, MyService.class), 0);

   long firstTime = SystemClock.elapsedRealtime();
   AlarmManager am = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);

   long intervalInSec = 4;

   am.setRepeating(AlarmManager.ELAPSED_REALTIME, firstTime, intervalInSec*1000, serviceIntent)

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