如何让ModalBottomSheetLayout在sheetContent中使用最新的状态？

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 StatefulWidget {
  @override
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  bool showSheet = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('ModalBottomSheetLayout Example'),
      ),
      body: Center(
        child: RaisedButton(
          child: Text('Show Modal Sheet'),
          onPressed: () {
            setState(() {
              showSheet = true;
            });
          },
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.add),
        onPressed: () {
          setState(() {
            showSheet = false;
          });
        },
      ),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
      bottomSheet: showSheet
          ? ModalBottomSheetLayout(
              builder: (BuildContext context) {
                return Container(
                  height: 200,
                  child: SheetContent(),
                );
              },
            )
          : null,
    );
  }
}

class SheetContent extends StatefulWidget {
  @override
  _SheetContentState createState() => _SheetContentState();
}

class _SheetContentState extends State<SheetContent> {
  int count = 0;

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        Text(
          'Count: $count',
          style: TextStyle(fontSize: 24),
        ),
        RaisedButton(
          child: Text('Increment'),
          onPressed: () {
            setState(() {
              count++;
            });
          },
        ),
      ],
    );
  }
}