18Flutter中的路由、路由替换、返回到根路由：

import 'package:flutter/material.dart';
class HomePage extends StatelessWidget {
  const HomePage({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      crossAxisAlignment: CrossAxisAlignment.center,
      children: [
        RaisedButton(
          child: Text('跳转到搜索页面'),
          onPressed: (){
            Navigator.pushNamed(context,'/search',arguments: {
              "id":123
            });
          },
          color: Theme.of(context).accentColor,
          textTheme: ButtonTextTheme.primary
        ),
        RaisedButton(
          child: Text('跳转到商品页面'),
          onPressed: (){
            Navigator.pushNamed(context,'/product');
          }
        )
      ],
    );
  }
}

import 'package:flutter/material.dart';

class ProductPage extends StatefulWidget {
  ProductPage({Key key}) : super(key: key);

  _ProductPageState createState() => _ProductPageState();
}

class _ProductPageState extends State {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('商品页面'),
        ),
        body: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            RaisedButton(
                child: Text('跳转到商品详情页面'),
                onPressed: () {
                  // Navigator.pushReplacementNamed(context, '/productinfo',
                  //     arguments: {"pid":778899}
                  // );
                  Navigator.pushNamed(context, '/productinfo',
                      arguments: {"pid":778899}
                  );
                },
                color: Theme.of(context).accentColor,
                textTheme: ButtonTextTheme.primary),
          ],
        )
        );
  }
}

import 'package:flutter/material.dart';
import '../pages/Tabs.dart';

class ProductInfoPage extends StatefulWidget {
  Map arguments;
  ProductInfoPage({Key key, this.arguments}) : super(key: key);

  _ProductInfoPageState createState() =>
      _ProductInfoPageState(arguments: this.arguments);
}

class _ProductInfoPageState extends State {
  Map arguments;
  _ProductInfoPageState({this.arguments});
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('商品详情页面'),
      ),
      // body: Text("这是一个商品详情页面pid=${arguments["pid"]}")
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          RaisedButton(
              child: Text('完成'),
              onPressed: () {
                // Navigator.of(context).pop();
                
                //返回根：
                Navigator.of(context).pushAndRemoveUntil(
                  new MaterialPageRoute(builder: (context)=>new Tabs(index: 1)),
                  (route)=>route==null
                );
              }
            ),
        ],
      ),
    );
  }
}

import 'package:flutter/material.dart';
import 'tabs/Home.dart';
import 'tabs/Category.dart';
import 'tabs/Setting.dart';
class Tabs extends StatefulWidget {
  final index;
  Tabs({Key key,this.index=0}) : super(key: key);
  _TabsState createState() => _TabsState(this.index);
}

class _TabsState extends State {
  int _currentIndex = 0;
  _TabsState(index){
    this._currentIndex=index;
  }
  List _pageList=[
    HomePage(),
    CategoryPage(),
    SettingPage()
  ];
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Flutter Demo'),
      ),
      bottomNavigationBar: BottomNavigationBar(
          currentIndex: this._currentIndex,
          onTap: (int index) {
            // print(index);
            setState(() {
              this._currentIndex = index;
            });
          },
          iconSize: 36.0,
          type: BottomNavigationBarType.fixed,
          fixedColor: Colors.red,
          items: [
            BottomNavigationBarItem(icon: Icon(Icons.home), title: Text('首页')),
            BottomNavigationBarItem(
                icon: Icon(Icons.category), title: Text('分类')),
            BottomNavigationBarItem(
                icon: Icon(Icons.settings), title: Text('设置')),
          ]),
      body: this._pageList[this._currentIndex],
    );
  }
}

import 'package:flutter/material.dart';
import 'package:flutter_demo/pages/Search.dart';
import 'routes/Routes.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      initialRoute: '/',
      onGenerateRoute: onGenerateRoute
      );
  }
}