如何在Flutter中没有上一个屏幕的appbar的情况下推送到新的屏幕？

import 'package:flutter/material.dart';

class NewScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('New Screen'),
      ),
      body: Center(
        child: Text('This is a new screen.'),
      ),
    );
  }
}

Navigator.push(
  context,
  MaterialPageRoute(builder: (context) => NewScreen()),
);