详解Flutter的路由导航

使用基本路由方式打开 Page1：
 Navigator.push(
        context, MaterialPageRoute(builder: (context) => Page1())),
        
 命名路由：
 void main() {
 runApp(MyApp());
}

class MyApp extends StatelessWidget {
 // This widget is the root of your application.
 @override
 Widget build(BuildContext context) {
  return MaterialApp(
   title: 'Flutter Demo',
   routes: {
   // 注册路由
    "route_Page1": (context) => Page1(),
    ...
   },
   onUnknownRoute: (RouteSettings setting) =>
     MaterialPageRoute(builder: (context) => ErrorPage()),
   theme: ThemeData(
    primarySwatch: Colors.blue,
    visualDensity: VisualDensity.adaptivePlatfORMDensity,
   ),
   home: MyHomePage(title: 'Flutter Demo Home Page'),
  );
 }
}
// 使用命名路由方式打开 Page1：
Navigator.pushNamed(context, "route_Page1"),

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

class MyApp extends StatelessWidget {
 // This widget is the root of your application.
 @override
 Widget build(BuildContext context) {
  return MaterialApp(
   title: 'Flutter Demo',
   routes: {
    "route_Page1": (context) => Page1(),
    ......
   },
   // 路由发生错误，进入到该指定页面
   onUnknownRoute: (RouteSettings setting) =>
     MaterialPageRoute(builder: (context) => ErrorPage()),
   theme: ThemeData(
    primarySwatch: Colors.blue,
    visualDensity: VisualDensity.adaptivePlatformDensity,
   ),
   home: MyHomePage(title: 'Flutter Demo Home Page'),
  );
 }
}

1. 传递参数：
 Navigator.pushNamed(context, "route_Page3", arguments: "hello"),
 2. 接收参数：
 
class Page3 extends StatelessWidget {
 @override
 Widget build(BuildContext context) {
  String msg = ModalRoute.of(context).settings.arguments as String;
  return Scaffold(
   backgroundColor: Colors.red,
   appBar: AppBar(
    title: Text("传递参数"),
   ),
   body: Text("得到的参数是:$msg"),
  );
 }
}
3， 参数的回传
class Page4 extends StatelessWidget {
 @override
 Widget build(BuildContext context) {
  String msg = ModalRoute.of(context).settings.arguments as String;
  return Scaffold(
   backgroundColor: Colors.yellow,
   appBar: AppBar(
    title: Text("返回参数"),
   ),
   body: Text("得到的参数是:$msg"),
   floatingActionButton: FloatingActionButton(
    child: Icon(Icons.backspace),
    onPressed: () => Navigator.pop(context, "hi"),
   ),
  );
 }
}
4. 回传参数的接收：通过then方法
 Navigator.pushNamed(context, "route_Page4", arguments: "hello")
          .then((value) => print("返回的参数是$value")),