Question

我正在尝试构建一个Android应用程序，该应用程序将每秒运行一次，当应用程序关闭或终止时，它也应在后台连续运行。当满足API响应条件时，它应显示本地通知。

我已将Service Class用于后台任务。除Oreo版本（8.1v）之外，所有版本都运行正常

我已经检查了网站以及与此相关的示例，发现关闭或终止该应用后，我们无法在 Oreo版本中执行后台任务。

所以我尝试使用startForeground（），但是它也没有用，经过多次尝试，最终我在这里问这个问题。

所以请帮助我在关闭应用程序后在后台运行API。

MainActivty.class

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            ContextCompat.startForegroundService(this, new Intent(this,MyService.class));
        } else {
            startService(new Intent(this,MyService.class));
        }
}

MyService.class

public class MyService extends Service {

    public static final int notify = 3000;  //interval between two services(Here Service run every 5 Minute)
    private Handler mHandler = new Handler();   //run on another Thread to avoid crash
    private Timer mTimer = null;    //timer handling

    @Override
    public IBinder onBind(Intent intent) {
        // TODO: Return the communication channel to the service.
        throw new UnsupportedOperationException("Not yet implemented");
    }

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

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

        if (mTimer != null) // Cancel if already existed
            mTimer.cancel();
        else
            mTimer = new Timer();   //recreate new
        mTimer.scheduleAtFixedRate(new TimeDisplay(), 0, notify);   //Schedule task

    }

    //class TimeDisplay for handling task
    class TimeDisplay extends TimerTask {
        @Override
        public void run() {
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    new ApiCallAsyncTask().execute(URL);
                }
            });
        }
    }
}

在ApiCallAsyncTask类中调用的通知方法

Notification notif;
@TargetApi(Build.VERSION_CODES.O)
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
public void notification(String Name, String time,String mId,int id){
    Intent intent = new Intent(MyService.this, MainActivity.class);
    String CHANNEL_ID = String.valueOf(id);

    PendingIntent pendingIntent = PendingIntent.getActivity(MyService.this, 100, intent, PendingIntent.FLAG_ONE_SHOT);
    NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {

        NotificationChannel mChannel = new NotificationChannel(CHANNEL_ID, Name, NotificationManager.IMPORTANCE_DEFAULT);
        notif = new Notification.Builder(MyService.this)
                .setContentIntent(pendingIntent)
                .setContentTitle("Reminder")
                .setContentText("hello")
                .setSmallIcon(R.drawable.logo)
                .setOnlyAlertOnce(true)
                .setColor(ContextCompat.getColor(MyService.this, R.color.colorPrimaryDark))
                .setChannelId(CHANNEL_ID)
                .build();
        notificationManager.createNotificationChannel(mChannel);
    }else {
        notif = new Notification.Builder(MyService.this)
                .setContentIntent(pendingIntent)
                .setContentTitle("Reminder")
                .setContentText("hello")
                .setSmallIcon(R.drawable.logo)
                .setOnlyAlertOnce(true)
                .setColor(ContextCompat.getColor(MyService.this, R.color.colorPrimaryDark))
                .build();

    }
    notif.flags |= Notification.FLAG_AUTO_CANCEL;
    notificationManager.notify(id, notif);
    startForeground(1, notif);
}

谢谢..

Answer 1

您可以结合使用JobIntentService + AlarmManager（用于计划）或JobScheduler API。

但我强烈建议您将您的方法替换为Firebase Cloud Messaging。因此，您将把业务逻辑放在服务器端，并在特殊情况下通知客户端。

在Oreo版本中杀死Android应用后，每秒在后台运行API

1 个答案: