Flutter:在运行的应用程序中获得显示模式(暗/正常)更改的通知

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Display Mode'),
        ),
        body: Center(
          child: DisplayModeWidget(),
        ),
      ),
    );
  }
}

class DisplayModeWidget extends StatefulWidget {
  @override
  _DisplayModeWidgetState createState() => _DisplayModeWidgetState();
}

class _DisplayModeWidgetState extends State<DisplayModeWidget> {
  Brightness _currentBrightness;

  @override
  void initState() {
    super.initState();
    _currentBrightness = MediaQuery.of(context).platformBrightness;
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        Text(
          'Current Display Mode:',
          style: TextStyle(fontSize: 20),
        ),
        SizedBox(height: 10),
        Text(
          _currentBrightness == Brightness.light ? 'Normal' : 'Dark',
          style: TextStyle(fontSize: 24, fontWeight: FontWeight.bold),
        ),
      ],
    );
  }
}