如何在flutter中向用户请求多个权限？

import 'package:flutter/material.dart';
import 'package:permission_handler/permission_handler.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: PermissionPage(),
    );
  }
}

class PermissionPage extends StatefulWidget {
  @override
  _PermissionPageState createState() => _PermissionPageState();
}

class _PermissionPageState extends State<PermissionPage> {
  Map<Permission, PermissionStatus> _permissions = {};

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

  Future<void> requestPermissions() async {
    List<Permission> permissions = [
      Permission.camera,
      Permission.microphone,
      Permission.location,
    ];

    Map<Permission, PermissionStatus> status = await PermissionHandler().requestPermissions(permissions);
    setState(() {
      _permissions = status;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Permission Demo'),
      ),
      body: ListView(
        children: _permissions.keys.map((permission) {
          return ListTile(
            title: Text(permission.toString()),
            subtitle: Text('Status: ${_permissions[permission]}'),
          );
        }).toList(),
      ),
    );
  }
}