fix: make EmptyShellRoute() a const

chores: add nested navigation example
chores: add declarative navigation example

README.md

@@ -415,6 +415,20 @@ AutoRoute(
 )
 ```
 
+or by using a `RedirectRoute`
+
+```dart
+AutoRoute(
+  path: '/dashboard',
+  page: DashboardRoute.page,
+  children: [
+    RedirectRoute(path: '', redirectTo: 'users'),
+    AutoRoute(path: 'users', page: UsersRoute.page),
+    AutoRoute(path: 'posts', page: PostsRoute.page),
+  ],
+)
+```
+
 #### Creating Empty Shell routes
 Empty shell routes build a screen that contain the `AutoRouter` widget, which is used to render nested routes.
 So you can build the widget your self like follows:
@@ -440,24 +454,12 @@ class MyShellPage extends AutoRouter {
 finally you can create a shell route without code generation using the `EmptyShellRoute` helper
 
   ```dart
-     final BooksTab = EmptyShellRoute('BooksTab');
+     const BooksTab = EmptyShellRoute('BooksTab');
      context.push(BooksTab());
   ```
 
 
-or by using a `RedirectRoute`
 
-```dart
-AutoRoute(
-  path: '/dashboard',
-  page: DashboardRoute.page,
-  children: [
-    RedirectRoute(path: '', redirectTo: 'users'),
-    AutoRoute(path: 'users', page: UsersRoute.page),
-    AutoRoute(path: 'posts', page: PostsRoute.page),
-  ],
-)
-```
 
 ### Things to keep in mind when implementing nested navigation
 
@@ -1539,9 +1541,10 @@ void initState(){
 
 
 ## Examples
-
+ 
 - [Declarative Navigation](https://github.com/Milad-Akarie/auto_route_library/blob/master/auto_route/example/lib/declarative/declarative.router.dart)
-
+- [Nested Navigation](https://github.com/Milad-Akarie/auto_route_library/blob/master/auto_route/example/lib/nested-navigation/nested_navigation.router.dart)
+
 ### Support auto_route
 
 You can support auto_route by liking it on Pub and staring it on Github, sharing ideas on how we can enhance a certain functionality or by reporting any problems you encounter and of course buying a couple coffees will help speed up the development process

auto_route/example/lib/mobile/router/router.dart

@@ -42,5 +42,5 @@ class AppRouter extends RootStackRouter {
   ];
 }
 
-final BooksTab = EmptyShellRoute('BooksTab');
-final ProfileTab = EmptyShellRoute('ProfileTab');
+const BooksTab = EmptyShellRoute('BooksTab');
+const ProfileTab = EmptyShellRoute('ProfileTab');

auto_route/example/lib/nested-navigation/nested_navigation.router.dart

@@ -0,0 +1,80 @@
+import 'package:auto_route/auto_route.dart';
+import 'package:example/nested-navigation/nested_navigation.router.gr.dart';
+import 'package:flutter/material.dart';
+
+void main() {
+  runApp(NestedNavigationApp());
+}
+
+class NestedNavigationApp extends StatelessWidget {
+  NestedNavigationApp({super.key});
+
+  final nestedRouter = NestedRouter();
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp.router(
+      routerConfig: nestedRouter.config(),
+    );
+  }
+}
+
+@AutoRouterConfig(generateForDir: ['lib/nested-navigation'])
+class NestedRouter extends RootStackRouter {
+  @override
+  List<AutoRoute> get routes => [
+        AutoRoute(
+          initial: true,
+          page: HostRoute.page,
+          children: [
+            AutoRoute(page: FirstRoute.page, initial: true),
+            AutoRoute(page: SecondRoute.page),
+          ],
+        ),
+      ];
+}
+
+@RoutePage()
+class HostScreen extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Host Screen'),
+        /// This will automatically display a back button if the nested router can pop
+        leading: AutoLeadingButton(),
+      ),
+      body: AutoRouter(),
+    );
+  }
+}
+
+@RoutePage()
+class FirstScreen extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: Center(
+        child: ElevatedButton(
+          onPressed: () => context.pushRoute(SecondRoute()),
+          child: Text('Go to second screen'),
+        ),
+      ),
+    );
+  }
+}
+
+@RoutePage()
+class SecondScreen extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: Center(
+        child: ElevatedButton(
+          onPressed: () => context.maybePop(),
+          child: Text('Go Back'),
+        ),
+      ),
+    );
+  }
+}

auto_route/lib/src/route/page_info.dart

@@ -9,10 +9,18 @@ class PageInfo {
   final String name;
 
   /// The builder function of the generated [RoutePage]
-  final Widget Function(RouteData data) builder;
+  final AutoRoutePageBuilder builder;
 
   /// Default constructor
-  const PageInfo(this.name, {required this.builder});
+  const PageInfo(this.name, {required this.builder}) ;
+
+/// Builds an empty shell [PageInfo] with a const builder
+  const PageInfo.emptyShell(this.name) : builder = _emptyShellBuilder;
+
+
+  static Widget _emptyShellBuilder(RouteData _){
+    return const AutoRouter();
+  }
 
   @override
   bool operator ==(Object other) =>

auto_route/lib/src/route/page_route_info.dart

@@ -197,18 +197,17 @@ class PageRouteInfo<T> {
 
 /// A proxy Route page that provides a way to create a [PageRouteInfo]
 /// without the need for creating a new Page Widget
-class EmptyShellRoute {
-  /// Page name
-  final String name;
+class EmptyShellRoute extends PageInfo {
 
   /// Default constructor
-  EmptyShellRoute(this.name);
-
-  /// creates [PageInfo] with an just an [AutoRouter] widget
-  late final page = PageInfo(name, builder: (_) => const AutoRouter());
+  const EmptyShellRoute(super.name) : super.emptyShell();
 
   /// Creates a new instance with of [PageRouteInfo]
   PageRouteInfo call({List<PageRouteInfo>? children}) {
     return PageRouteInfo(name, initialChildren: children);
   }
+
+  /// Creates a new instance with of [PageInfo] with an empty shell builder
+  /// that returns an [AutoRouter] widget
+  PageInfo get page => this;
 }