Question

我无法理解android有关服务的新功能。在Google文档中，oreo之后，当应用程序在后台运行时，开发人员必须使用前台服务来启动服务。

我找到了这些描述。

'从Android O开始，如果您的应用程序处于后台运行（请检查以上三个条件），则您的应用程序可以在几分钟内创建并运行后台服务。

经过几分钟，您的应用程序将进入空闲阶段。当您的应用程序进入空闲阶段时，系统将停止所有后台服务，就像您的服务调用Service.stopSelf()一样。”

我无法理解，即使我以START_STICKY开始服务，也不会再次开始吗？我知道如果我以START_STICKY开头，它将在kill之后完全重启。为什么我必须使用JobScheduler来满足某些需求（位置更新等）。有人可以解释一下。我不太了解google文档。

我现在在galaxy note 8 api26手机上对其进行测试。我在应用启动时通过startService启动服务，而在关闭应用后又重新启动。旧版本之间有什么区别

谢谢。

Answer 1

ublic class MyActivity2 extends Activity {

private Intent serviceIntent;

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    serviceIntent = new Intent(this, MyService.class);
    serviceIntent.putExtra("name", "ahmet vefa saruhan");
    startService(serviceIntent);
    findViewById(R.id.textview).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            stopService(new Intent(getApplicationContext(),MyService.class));
        }
    });
}

}

public class MyService extends Service {

private String myaction;

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

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    Log.d("MYSERVICE STATUS: "," ONSTARTCOMMAND action : " + ((intent != null && intent.getStringExtra("name") != null) ? intent.getStringExtra("name") : "yok") + " OLD ACTION : "+(myaction != null ? myaction : "yok"));
    Log.d("MYTHREAD name : ",Thread.currentThread().getName());
    //intent.putExtra("name","isim değişti");
    myaction = (intent != null) ? intent.getAction() : null;
    return START_STICKY;
}

@Override
public void onCreate() {
    super.onCreate();
   Log.d("MYSERVICE STATUS: "," ONCREATED");
}

@RequiresApi(api = Build.VERSION_CODES.O)
private void startMyOwnForeground()
{
    String NOTIFICATION_CHANNEL_ID = "example.permanence";
    String channelName = "Background Service";
    NotificationChannel chan = new NotificationChannel(NOTIFICATION_CHANNEL_ID, channelName, NotificationManager.IMPORTANCE_NONE);
    chan.setLightColor(Color.BLUE);
    chan.setLockscreenVisibility(Notification.VISIBILITY_PRIVATE);

    NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    assert manager != null;
    manager.createNotificationChannel(chan);

    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID);
    Notification notification = notificationBuilder.setOngoing(true)
            .setContentTitle("App is running in background")
            .setPriority(NotificationManager.IMPORTANCE_MIN)
            .setCategory(Notification.CATEGORY_SERVICE)
            .build();
    startForeground(2, notification);
}

@Override
public void onDestroy() {
    Log.d("MYSERVICE STATUS: "," ONDESTROYED");
    super.onDestroy();
}

@Override
public void onTaskRemoved(Intent rootIntent) {
    Log.d("MYSERVICE STATUS: "," onTaskRemoved");
    super.onTaskRemoved(rootIntent);
}

}

android使用START_STICKY

1 个答案: