如何在Flutter中实现这个时间选择器UI？

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Time Picker Example',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  DateTime _selectedDate;

  @override
  void initState() {
    super.initState();
    _selectedDate = DateTime.now();
  }

  Future<void> _showDatePicker() async {
    final DateTime pickedDate = await showDatePicker(
      context: context,
      initialDate: _selectedDate,
      firstDate: DateTime(2010),
      lastDate: DateTime(2030),
    );

    if (pickedDate != null && pickedDate != _selectedDate) {
      setState(() {
        _selectedDate = pickedDate;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Time Picker Example'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text(
              'Selected Date: ${_selectedDate.toString()}',
              style: TextStyle(fontSize: 18),
            ),
            SizedBox(height: 20),
            RaisedButton(
              onPressed: _showDatePicker,
              child: Text('Select Date'),
            ),
          ],
        ),
      ),
    );
  }
}