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我正在尝试用颤振实现主屏幕小部件，这是我尝试使用home_widget的包，但不幸的是我遇到了一些我无法理解的异常。这是我的代码，

import 'dart:async';
import 'dart:io';
import 'dart:math';

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:home_widget/home_widget.dart';
import 'package:workmanager/workmanager.dart';

/// Used for Background Updates using Workmanager Plugin
void callbackDispatcher() {
  Workmanager().executeTask((taskName, inputData) {
    final now = DateTime.now();
    return Future.wait<bool?>([
      HomeWidget.saveWidgetData(
        'title',
        'Updated from Background',
      ),
      HomeWidget.saveWidgetData(
        'message',
        '${now.hour.toString().padLeft(2, '0')}:${now.minute.toString().padLeft(2, '0')}',
      ),
      HomeWidget.updateWidget(
        name: 'HomeWidgetExampleProvider',
        iOSName: 'HomeWidgetExample',
      ),
    ]).then((value) {
      return !value.contains(false);
    });
  });
}

/// Called when Doing Background Work initiated from Widget
void backgroundCallback(var data) async {
  print(data);

  if (data.host == 'titleclicked') {
    final greetings = [
      'Hello',
      'Hallo',
      'Bonjour',
      'Hola',
      'Ciao',
      '哈洛',
      '안녕하세요',
      'xin chào'
    ];
    final selectedGreeting = greetings[Random().nextInt(greetings.length)];

    await HomeWidget.saveWidgetData<String>('title', selectedGreeting);
    await HomeWidget.updateWidget(
        name: 'HomeWidgetExampleProvider', iOSName: 'HomeWidgetExample');
  }
}

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  Workmanager().initialize(callbackDispatcher, isInDebugMode: kDebugMode);
  runApp(MaterialApp(home: MyApp()));
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final TextEditingController _titleController = TextEditingController();
  final TextEditingController _messageController = TextEditingController();

  @override
  void initState() {
    super.initState();
    HomeWidget.setAppGroupId('YOUR_GROUP_ID');
    HomeWidget.registerBackgroundCallback(backgroundCallback);
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _checkForWidgetLaunch();
    HomeWidget.widgetClicked.listen(_launchedFromWidget);
  }

  @override
  void dispose() {
    _titleController.dispose();
    _messageController.dispose();
    super.dispose();
  }

  Future _sendData() async {
    try {
      return Future.wait([
        HomeWidget.saveWidgetData<String>('title', _titleController.text),
        HomeWidget.saveWidgetData<String>('message', _messageController.text),
      ]);
    } on PlatformException catch (exception) {
      debugPrint('Error Sending Data. $exception');
    }
  }

  Future _updateWidget() async {
    try {
      return HomeWidget.updateWidget(
          name: 'HomeWidgetExampleProvider', iOSName: 'HomeWidgetExample');
    } on PlatformException catch (exception) {
      debugPrint('Error Updating Widget. $exception');
    }
  }

  Future _loadData() async {
    try {
      return Future.wait([
        HomeWidget.getWidgetData<String>('title', defaultValue: 'Default Title')
            .then((value) => _titleController.text = value.toString()),
        HomeWidget.getWidgetData<String>('message',
                defaultValue: 'Default Message')
            .then((value) => _messageController.text = value.toString()),
      ]);
    } on PlatformException catch (exception) {
      debugPrint('Error Getting Data. $exception');
    }
  }

  Future<void> _sendAndUpdate() async {
    await _sendData();
    await _updateWidget();
  }

  void _checkForWidgetLaunch() {
    HomeWidget.initiallyLaunchedFromHomeWidget().then(_launchedFromWidget);
  }

  void _launchedFromWidget(var uri) {
    if (uri != null) {
      showDialog(
          context: context,
          builder: (buildContext) => AlertDialog(
                title: Text('App started from HomeScreenWidget'),
                content: Text('Here is the URI: $uri'),
              ));
    }
  }

  void _startBackgroundUpdate() {
    Workmanager().registerPeriodicTask('1', 'widgetBackgroundUpdate',
        frequency: Duration(minutes: 15));
  }

  void _stopBackgroundUpdate() {
    Workmanager().cancelByUniqueName('1');
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('HomeWidget Example'),
      ),
      body: Center(
        child: Column(
          children: [
            TextField(
              decoration: InputDecoration(
                hintText: 'Title',
              ),
              controller: _titleController,
            ),
            TextField(
              decoration: InputDecoration(
                hintText: 'Body',
              ),
              controller: _messageController,
            ),
            ElevatedButton(
              onPressed: _sendAndUpdate,
              child: Text('Send Data to Widget'),
            ),
            ElevatedButton(
              onPressed: _loadData,
              child: Text('Load Data'),
            ),
            ElevatedButton(
              onPressed: _checkForWidgetLaunch,
              child: Text('Check For Widget Launch'),
            ),
            if (Platform.isAndroid)
              ElevatedButton(
                onPressed: _startBackgroundUpdate,
                child: Text('Update in background'),
              ),
            if (Platform.isAndroid)
              ElevatedButton(
                onPressed: _stopBackgroundUpdate,
                child: Text('Stop updating in background'),
              )
          ],
        ),
      ),
    );
  }
}

这是我得到的例外，

E/flutter (16907): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: PlatformException(error, java.lang.Integer cannot be cast to java.lang.Long, null, java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long
E/flutter (16907):      at es.antonborri.home_widget.HomeWidgetPlugin.onMethodCall(HomeWidgetPlugin.kt:105)
E/flutter (16907):      at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/flutter (16907):      at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)    
E/flutter (16907):      at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:818)
E/flutter (16907):      at android.os.MessageQueue.nativePollOnce(Native Method)
E/flutter (16907):      at android.os.MessageQueue.next(MessageQueue.java:336)
E/flutter (16907):      at android.os.Looper.loop(Looper.java:174)
E/flutter (16907):      at android.app.ActivityThread.main(ActivityThread.java:7356)
E/flutter (16907):      at java.lang.reflect.Method.invoke(Native Method)
E/flutter (16907):      at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
E/flutter (16907):      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
E/flutter (16907): )
E/flutter (16907): #0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:597:7)    
E/flutter (16907): #1      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:158:18)        
E/flutter (16907): <asynchronous suspension>
E/flutter (16907):

异常说“PlatformException（error，java.lang.Integer cannot be cast to java.lang.Long, null, java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long”是我能做到的不明白。我也复制并粘贴了确切的文档代码，但它包含一些我在上面给出的代码中更正的错误。任何帮助都会很棒。谢谢

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