Question

我遇到了问题。每隔一段时间，IntentService UpdateService02就无法运行。我把日志条目放进去，所以我可以调试，这就是我得到的......

02-28 21：37：32.461：主要 - 发送广播

02-28 21：37：32.484：BroadcastReceiver - 主要开始;设置闹钟

02-28 21：37：32.539：BroadcastReceiver - 收到AlarmService

02-28 21：38：32.500：BroadcastReceiver - 收到AlarmService

通常会发生这种情况：

02-28 21：37：32.461：主要 - 发送广播

02-28 21：37：32.484：BroadcastReceiver - 主要开始;设置闹钟

02-28 21：37：32.539：BroadcastReceiver - 收到AlarmService

02-28 21：38：32.500：UpdateService - onHandleIntent（）

有什么想法吗？这是我的广播接收器代码......

广播接收器：

public class AlarmReceiver extends BroadcastReceiver {

    private static final int INTERVAL = 60*1000; // check every 60 seconds

    @Override
    public void onReceive(Context context, Intent intent) {
        if(intent.getAction() != null) {
            if (intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED)) {
                Log.v(TAG, "BroadcastReceiver - Received Boot Completed; Set Alarm");

                setRecurringAlarm(context);
            }else if(intent.getAction().equalsIgnoreCase(Main.BROADCAST_STARTUP)){
                Log.v(TAG, "BroadcastReceiver - Main Started; Set Alarm");

                setRecurringAlarm(context);
            }else{
                Log.v(TAG, "BroadcastReceiver - Received " + intent.getAction());
            }
        }else{
            Log.v(TAG, "BroadcastReceiver - Received AlarmService");

            Intent i = new Intent(context, UpdateService02.class);
            context.startService(i);
        }
    }

    private void setRecurringAlarm(Context context) {
        Intent receiver = new Intent(context, AlarmReceiver.class);
        PendingIntent recurringDownload = PendingIntent.getBroadcast(context, 0, receiver, PendingIntent.FLAG_CANCEL_CURRENT);
        AlarmManager alarms = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        alarms.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), INTERVAL, recurringDownload);
    }
}

意图服务：

public class UpdateService02 extends IntentService {

    static DefaultHttpClient mClient = Client.getClient();
    private static final int LIST_UPDATE_NOTIFICATION = 100;

    public UpdateService02() {
        super("UpdateService02");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        Log.v(TAG, "UpdateService -- onHandleIntent()");

        try {
            HttpGet httpget = new HttpGet(url);
            HttpResponse response;
            response = mClient.execute(httpget);
            BufferedReader in = new BufferedReader (new InputStreamReader(response.getEntity().getContent()));

            Intent i = new Intent(BROADCAST_UPDATE);  
            i.putExtra("text", in.readLine().toString() + " updated");
            sendBroadcast(i);
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

我认为可能需要将intentservice启动的上下文设置为应用程序，但老实说我不知道。

Answer 1

我发现了问题......

我改变了这个：

try {
    HttpGet httpget = new HttpGet(url);
    HttpResponse response;
    response = mClient.execute(httpget);
    BufferedReader in = new BufferedReader (new InputStreamReader(response.getEntity().getContent()));

    Intent i = new Intent(BROADCAST_UPDATE);  
    i.putExtra("text", in.readLine().toString() + " updated");
    sendBroadcast(i);
} catch (ClientProtocolException e) {

到此：

try {
    HttpGet httpget = new HttpGet(url);
    HttpResponse response;
    response = mClient.execute(httpget);
    BufferedReader in = new BufferedReader (new InputStreamReader(response.getEntity().getContent()));

    Intent i = new Intent(BROADCAST_UPDATE);  
    i.putExtra("text", in.readLine().toString() + " updated");
    sendBroadcast(i);
    in.close();
} catch (ClientProtocolException e) {

有时候读者会被“堵塞”，下次被调用时，它仍然会被困在试图处理最后一个请求。添加in.close();确保我在每次使用后关闭它。现在效果很好。

Answer 2

服务只会启动一次。如果为已启动的服务调用startService（），则不会产生任何影响。请参阅http://developer.android.com/guide/topics/fundamentals/services.html。

A service is "started" when an application component (such as an activity) starts it by
calling startService(). Once started, a service can run in the background indefinitely,
even if the component that started it is destroyed.

当服务未运行时，意图应该正常工作。

关于

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在某些情况下，IntentService无法运行

2 个答案: