Flutter 中的导航

我正在学习使用颤振并决定处理路线（路线）。面临以下问题：

我有几个屏幕：Screen_1，Screen_2，Screen_3。从Screen_1我去Screen_2，从那里到Screen_3，从那里回到Screen_1。现在，当我按下“返回”键时，它会从 Screen_1 返回到Screen_3 ，然后返回到Screen_2 ，依此类推。问题是如何做到这一点，如果我从Screen_3返回到Screen_1，那么当我按下“返回”键时，我无法返回到Screen_3？以及如何去掉这个箭头“返回”的显示在屏幕顶部？

示例： 视频

动图：

路线代码：

import 'package:flutter/material.dart';
import 'package:quest/Screens/Endings/endings.dart';
import 'package:quest/Screens/NewGame/levelChoice.dart';
import 'package:quest/Screens/NewGame/newGame.dart';
import 'package:quest/Screens/Settings/settings.dart';
import 'package:quest/main.dart';

final routes = {
  '/': (BuildContext context) => new MyApp(),
  '/Endings': (BuildContext context) => new EndingsScreen(),
  '/LevelChoice': (BuildContext context) => new LevelChoiceScreen(),
  '/NewGame': (BuildContext context) => new NewGameScreen(),
  '/Settings': (BuildContext context) => new SettingsScreen()
};

main.dart 代码

import 'package:flutter/material.dart';
import 'package:quest/Config/Routes.dart';
import 'package:quest/Config/UiData.dart';

void main() {
  runApp(MaterialApp(
    title: UiData.AppName,
    debugShowCheckedModeBanner: false,
    initialRoute: '/',
    routes: routes,
  ));
}

class MyApp extends StatelessWidget {

  @override
  Widget build(BuildContext context) {

    UiData.deviceSize = MediaQuery.of(context).size;

    return Scaffold(
      appBar: AppBar(
        title: Text(UiData.AppName + " " + UiData.AppVersion),
      ),

      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[

            Container(
              height: UiData.deviceSize.height / 5,
              width: UiData.deviceSize.width,

              child: Center(
                child: Text(UiData.AppName,
                  style: new TextStyle(
                    fontSize: 100.0,
                    fontFamily: 'MainFonts',
                    color: Colors.black,
                  ),
                ),
              )
            ),

            Container(
              height: UiData.deviceSize.height / 10,
              width: UiData.deviceSize.width / 2,
              padding: EdgeInsets.all(5.0),

              child: MaterialButton(
                height: UiData.deviceSize.height / 10,
                minWidth: UiData.deviceSize.width / 2,
                color: Theme.of(context).primaryColor,
                textColor: Colors.white,
                child: new Text(
                  "Новая игра",
                  style: new TextStyle(
                    fontSize: 25.0,
                    fontFamily: 'ButtonFonts',
                    color: Colors.yellow,
                  ),
                ),
                onPressed: () {
                  Navigator.pushNamed(context, '/LevelChoice');
                },
                splashColor: Colors.redAccent,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

等级选择代码：

import 'package:flutter/material.dart';
import 'package:quest/Config/UiData.dart';

class LevelChoiceScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Выбор уровня"),
      ),
      body: Center(
        child: ListView(
          children: <Widget>[

            Container(
              height: UiData.deviceSize.height / 10,
              width: UiData.deviceSize.width / 2,
              padding: EdgeInsets.all(5.0),

              child: MaterialButton(
                height: UiData.deviceSize.height / 10,
                minWidth: UiData.deviceSize.width / 2,
                color: Theme.of(context).primaryColor,
                textColor: Colors.white,
                child: new Text(
                  "Акт 1",
                  style: new TextStyle(
                    fontSize: 25.0,
                    fontFamily: 'ButtonFonts',
                    color: Colors.yellow,
                  ),
                ),
                onPressed: () {
                  Navigator.pushNamed(context, '/NewGame');
                },
                splashColor: Colors.redAccent,
              ),
            ),

            RaisedButton(
              onPressed: () {
                Navigator.pop(context);
              },
              child: Text('Go back!'),
            ),
          ],
        ),
      ),
    );
  }
}

新游戏代码：

import 'package:flutter/material.dart';

class NewGameScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Новая игра"),
      ),
      body: Center(
        child: RaisedButton(
          onPressed: () {
            Navigator.pushNamed(context, '/');
          },
          child: Text('Go back!'),
        ),
      ),
    );
  }
}