如何在flutter上从CupertinoTimerPicker inside showModalBottomSheet返回数据？

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

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

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

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Flutter CupertinoTimerPicker'),
      ),
      body: Center(
        child: RaisedButton(
          child: Text('Open Timer Picker'),
          onPressed: () {
            showModalBottomSheet(
              context: context,
              builder: (BuildContext builder) {
                return Container(
                  height: MediaQuery.of(context).copyWith().size.height / 3,
                  child: CupertinoTimerPicker(
                    mode: CupertinoTimerPickerMode.hms,
                    onTimerDurationChanged: (Duration duration) {
                      Navigator.pop(context, duration);
                    },
                  ),
                );
              },
            );
          },
        ),
      ),
    );
  }
}