在Android 9之后，当手机进入待机模式时，带通知的前台服务可能会被系统停止。为了解决这个问题，可以采用以下代码示例中的方法：

1. 在AndroidManifest.xml文件中添加以下权限：

2. 在你的Service类中，添加以下代码：

public class MyForegroundService extends Service {

    private static final String CHANNEL_ID = "ForegroundServiceChannel";

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

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        String input = intent.getStringExtra("inputExtra");
        Notification notification = createNotification(input);
        startForeground(1, notification);
        // 执行你的任务逻辑
        return START_NOT_STICKY;
    }

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

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

    private void createNotificationChannel() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel serviceChannel = new NotificationChannel(
                    CHANNEL_ID,
                    "Foreground Service Channel",
                    NotificationManager.IMPORTANCE_DEFAULT
            );
            NotificationManager manager = getSystemService(NotificationManager.class);
            manager.createNotificationChannel(serviceChannel);
        }
    }

    private Notification createNotification(String input) {
        Intent notificationIntent = new Intent(this, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(this,
                0, notificationIntent, 0);

        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, CHANNEL_ID)
                .setContentTitle("Foreground Service")
                .setContentText(input)
                .setSmallIcon(R.drawable.ic_notification)
                .setContentIntent(pendingIntent);

        return builder.build();
    }
}

3. 在你的Activity或者其他地方，启动该Service：

Intent serviceIntent = new Intent(this, MyForegroundService.class);
serviceIntent.putExtra("inputExtra", "Foreground Service Example");
ContextCompat.startForegroundService(this, serviceIntent);

通过使用上述代码示例中的方法，你可以确保即使在Android 9及更高版本中，带通知的前台服务也能在手机进入待机模式后继续运行。