关闭应用程序后无法在通知栏中显示计数器

Question

我正在尝试创建一个可以在关闭应用程序时运行的秒表应用程序。我尝试了这段代码，但是当应用程序关闭（正常）时，循环停止了。有什么办法可以实现这个目标。平台不允许每秒运行后台服务。

int counter = 0;
  Future<void> _showProgressNotification() async {
    var maxProgress = 25;
    counter = 0;
    for (var i = 0; i <= maxProgress; i++) {
      counter++;
      await Future.delayed(Duration(seconds: 1), () async {
        var androidPlatformChannelSpecifics = AndroidNotificationDetails(
            'progress channel',
            'progress channel',
            'progress channel description',
            channelShowBadge: false,
            importance: Importance.Max,
            priority: Priority.High,
            onlyAlertOnce: true,
            showProgress: false,
            maxProgress: maxProgress,
            progress: i);
        var iOSPlatformChannelSpecifics = IOSNotificationDetails();
        var platformChannelSpecifics = NotificationDetails(
            androidPlatformChannelSpecifics, iOSPlatformChannelSpecifics);
        await flutterLocalNotificationsPlugin.show(
            0,
            "Kronometre - Anatomi",
            "Süre: $counter",
            platformChannelSpecifics,
            payload: 'item x');
      });
    }
  }