Flutter自定义页面路线和iOS向后滑动手势

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
      routes: {
        '/second': (context) => SecondPage(),
        '/third': (context) => ThirdPage(),
      },
    );
  }
}

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Home'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            RaisedButton(
              child: Text('Go to Second Page'),
              onPressed: () {
                Navigator.pushNamed(context, '/second');
              },
            ),
          ],
        ),
      ),
    );
  }
}

class SecondPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Second Page'),
      ),
      body: GestureDetector(
        onHorizontalDragEnd: (DragEndDetails details) {
          if (details.primaryVelocity < 0) {
            Navigator.pop(context);
          }
        },
        child: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Text('Swipe right to go back'),
              RaisedButton(
                child: Text('Go to Third Page'),
                onPressed: () {
                  Navigator.pushNamed(context, '/third');
                },
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class ThirdPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Third Page'),
      ),
      body: Center(
        child: RaisedButton(
          child: Text('Go back'),
          onPressed: () {
            Navigator.pop(context);
          },
        ),
      ),
    );
  }
}