安卓后台服务在一段时间后停止

Question

我创建了一个后台服务，它定期打到我的服务器，但不幸的是，后台服务在一段时间后停止。

public class LocationService extends Service{ 

@Override 
public int onStartCommand(Intent intent, int flags, int startId) { 

    //TODO do something useful 

     new DownloadFilesTask().execute(""); 
     Toast.makeText(getApplicationContext(), "start", Toast.LENGTH_SHORT).show(); 

    return START_STICKY; 
} 


private class DownloadFilesTask extends AsyncTask<String, Void, String> { 
    @Override 
    protected String doInBackground(String... params) { 

    try { 
     URL url = new URL(siteurl); 
     HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection(); 
     try { 
      BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream())); 
      StringBuilder stringBuilder = new StringBuilder(); 
      String line; 
      while ((line = bufferedReader.readLine()) != null) { 
       stringBuilder.append(line).append("\n"); 
      } 
      bufferedReader.close(); 
      return stringBuilder.toString(); 

     } 
     finally{ 
      urlConnection.disconnect(); 
     } 
    } 
    catch(Exception e) { 
     Log.e("ERROR", e.getMessage(), e); 
     return null; 
    } 

    } 

    @Override 
    protected void onPostExecute(String result) { 
    } 

    @Override 
    protected void onPreExecute() { 
    } 

    @Override 
    protected void onProgressUpdate(Void... values) { 
    } 
} 

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

@Override 
public void onDestroy() { 
    super.onDestroy(); 

    Intent myIntent = new Intent(getApplicationContext(), LocationService.class); 

PendingIntent pendingIntent = PendingIntent.getService(getApplicationContext(), 0, myIntent, 0); 

AlarmManager alarmManager1 = (AlarmManager) getSystemService(ALARM_SERVICE); 


alarmManager1.cancel(pendingIntent); 
Calendar calendar = Calendar.getInstance(); 

calendar.setTimeInMillis(System.currentTimeMillis()); 

calendar.add(Calendar.SECOND, 10); 

alarmManager1.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); 
alarmManager1.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_FIFTEEN_MINUTES, pendingIntent); 

} 
@Override 
public void onTaskRemoved(Intent rootIntent) { 
    super.onTaskRemoved(rootIntent); 

    Intent myIntent = new Intent(getApplicationContext(), LocationService.class); 

PendingIntent pendingIntent = PendingIntent.getService(getApplicationContext(), 0, myIntent, 0); 

AlarmManager alarmManager1 = (AlarmManager) getSystemService(ALARM_SERVICE); 


alarmManager1.cancel(pendingIntent); 
Calendar calendar = Calendar.getInstance(); 

calendar.setTimeInMillis(System.currentTimeMillis()); 

calendar.add(Calendar.SECOND, 10); 

alarmManager1.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); 
alarmManager1.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_FIFTEEN_MINUTES, pendingIntent); 


} 

} 

Answer 1

随着最新版本的Android API级别26，对后台服务有限制。请参阅Background execution limits

Answer 2

只有在代码的任何位置调用startService时，onStartCommand才会自动撤销。因此仅在Manifest中声明服务是不够的。

所以，通过调用

startService(new Intent(context, serviceName.class)); 

按照上面的代码onStartCommand方法将定期撤销如果服务没有停止运行的服务。

有关您的信息，请从近期关闭服务中删除应用程序。并且

@Override 
public void onTaskRemoved(Intent rootIntent) { 

} 

方法正在被调用。

如果您手动启动服务，即使正在关闭，它也会自动重新启动。

Answer 3

定义广播接收器在这篇文章中调用您的服务。

https://stackoverflow.com/a/9092324/4409623