simple page route in flutter. Not refactored

page_route.dart

import 'package:flutter/material.dart';

void main() {
  runApp(
    MaterialApp(
      theme: themeData,
      home: Scaffold(
        body: MyApp(),
      ),
    ),
  );
}

final ThemeData themeData = ThemeData(
  canvasColor: Colors.lightBlueAccent,
  accentColor: Colors.redAccent,
);

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: FlatButton(
          child: Text("Go to page Two"),
          onPressed: () {
            Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => PageTwo(),
              ),
            );
          },
        ),
      ),
    );
  }
}

class PageTwo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: themeData.accentColor,
        elevation: 1.0,
      ),
      body: Center(
        child: RaisedButton(
          child: Text("Go to page Three"),
          onPressed: () {
            Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => PageThree(),
              ),
            );
          },
        ),
      ),
    );
  }
}

class PageThree extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: themeData.canvasColor,
        elevation: 1.0,
        title: Text("Last Page"),
      ),
      body: Center(
        child: FloatingActionButton(
          child: Text("Go back to home"),
          onPressed: () {
            Navigator.popUntil(
              context,
              ModalRoute.withName(Navigator.defaultRouteName),
            );
          },
        ),
      ),
    );
  }
}