Flutter Android Alarm Manager插件无法正常工作

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:android_alarm_manager/android_alarm_manager.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await AndroidAlarmManager.initialize();
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Alarm Manager Example')),
        body: Center(
          child: ElevatedButton(
            onPressed: () async {
              final id = 0;
              final now = DateTime.now();
              final scheduledDate = DateTime(now.year, now.month, now.day, 8, 30);
              await AndroidAlarmManager.oneShotAt(scheduledDate, id, exact: true);
              print('Alarm set for ${scheduledDate.toString()}');
            },
            child: Text('Set Alarm'),
          ),
        ),
      ),
    );
  }
}