如何在Build Widget中使用Navigator进行重定向

import 'package:flutter/material.dart';

class MyHomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('HomePage'),
      ),
      body: Center(
        child: RaisedButton(
          child: Text('跳转到详情页'),
          onPressed: () {
            Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => DetailPage(),
              ),
            );
          },
        ),
      ),
    );
  }
}

class DetailPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('DetailPage'),
      ),
      body: Center(
        child: RaisedButton(
          child: Text('返回首页'),
          onPressed: () {
            Navigator.pop(context);
          },
        ),
      ),
    );
  }
}