مشكلة تشغيل workmanager على ios flutter

السلام عليكم ورحمة الله وبركاته

تحيه طيبه للجميع

قمت بعمل نموذج مشروع لتشغيل workmanager لجعل التطبيق يعمل في الخلفية اثناء ما المستخدم خارج التطبيق المشكلة الان التطبيق على الاندرويد شغال ولكن مع تشغيله في ios ومحاكي على الماك تظهر المكله التاليه:

[VERBOSE-2:ui_dart_state.cc(166)] Unhandled Exception: MissingPluginException(No implementation found for method initialize on channel be.tramckrijte.workmanager/foreground_channel_work_manager)
#0      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:159:7)
<asynchronous suspension>
#1      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:334:12)
#2      Workmanager.initialize (package:workmanager/src/workmanager.dart:100:30)
#3      _MyHomePageState.initState (package:toios/main.dart:58:17)
#4      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4684:58)
#5      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4520:5)
#6      Element.inflateWidget (package:flutter/src/widgets/framework.dart:3490:14)
#7      Element.updateChild (package:flutter/src/widgets/framework.dart:3258:18)
#8      SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5874:14)
#9      Element.inflat<…>
[VERBOSE-2:ui_dart_state.cc(166)] Unhandled Exception: MissingPluginException(No implementation found for method registerPeriodicTask on channel be.tramckrijte.workmanager/foreground_channel_work_manager)
#0      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:159:7)
<asynchronous suspension>
#1      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:334:12)
#2      Workmanager.registerPeriodicTask (package:workmanager/src/workmanager.dart:158:32)
#3      _MyHomePageState.initState (package:toios/main.dart:63:17)
#4      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4684:58)
#5      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4520:5)
#6      Element.inflateWidget (package:flutter/src/widgets/framework.dart:3490:14)
#7      Element.updateChild (package:flutter/src/widgets/framework.dart:3258:18)
#8      SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5874:14)
#9<…>

وصفحات الكود كامل كالتالي انا عاملها:

import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
import 'package:workmanager/workmanager.dart';
import 'package:toios/notification.dart' as notif;

const fetchBackground = "fetchBackground";

void callbackDispatcher() {
  Workmanager.executeTask((task, inputData) async {
    switch (task) {
      case fetchBackground:
        //Geolocator geoLocator = Geolocator()..forceAndroidLocationManager = true;
        Position userLocation = await Geolocator().getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
        notif.Notification notification = new notif.Notification();
        notification.showNotificationWithoutSound(userLocation);
        break;
    }
    return Future.value(true);
  });
}


void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(

        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  @override
  void initState() {
    super.initState();

    // We don't need it anymore since it will be executed in background
    //this._getUserPosition();

    Workmanager.initialize(
      callbackDispatcher,
      isInDebugMode: true,
    );

    Workmanager.registerPeriodicTask(
        "1",
        fetchBackground,
        frequency: Duration(minutes: 30),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              "",
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
    );
  }
}

import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:geolocator/geolocator.dart';

class Notification {

  FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;

  Future showNotificationWithoutSound(Position position) async {
    print(position.toString());
    var androidPlatformChannelSpecifics = new AndroidNotificationDetails(
        '1', 'location-bg', 'fetch location in background',
        playSound: false, importance: Importance.Max, priority: Priority.High);
    var iOSPlatformChannelSpecifics =
    new IOSNotificationDetails(presentSound: false);
    var platformChannelSpecifics = new NotificationDetails(
        androidPlatformChannelSpecifics, iOSPlatformChannelSpecifics);
    await flutterLocalNotificationsPlugin.show(
      0,
      'Location fetched',
      position.toString(),
      platformChannelSpecifics,
      payload: '',
    );
  }

  Notification() {
    var initializationSettingsAndroid = new AndroidInitializationSettings('@mipmap/ic_launcher');
    var initializationSettingsIOS = new IOSInitializationSettings();
    var initializationSettings = new InitializationSettings(
        initializationSettingsAndroid, initializationSettingsIOS);
    flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();
    flutterLocalNotificationsPlugin.initialize(initializationSettings);
  }
}

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