[go_router_builder] add support to go_router_builder for initializing a ShellRoute with observers

packages/go_router_builder/CHANGELOG.md

@@ -1,5 +1,6 @@
-## NEXT
+## 2.4.0
 
+* Adds support for passing observers to the ShellRoute for the nested Navigator.
 * Updates minimum supported SDK version to Flutter 3.10/Dart 3.0.
 
 ## 2.3.4

packages/go_router_builder/example/lib/shell_route_with_observers_example.dart

@@ -0,0 +1,170 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ignore_for_file: public_member_api_docs
+
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+part 'shell_route_with_observers_example.g.dart';
+
+void main() => runApp(App());
+
+class App extends StatelessWidget {
+  App({super.key});
+
+  @override
+  Widget build(BuildContext context) => MaterialApp.router(
+        routerConfig: _router,
+      );
+
+  final GoRouter _router = GoRouter(
+    routes: $appRoutes,
+    initialLocation: '/home',
+  );
+}
+
+@TypedShellRoute<MyShellRouteData>(
+  routes: <TypedRoute<RouteData>>[
+    TypedGoRoute<HomeRouteData>(path: '/home'),
+    TypedGoRoute<UsersRouteData>(
+      path: '/users',
+      routes: <TypedGoRoute<UserRouteData>>[
+        TypedGoRoute<UserRouteData>(path: ':id'),
+      ],
+    ),
+  ],
+)
+class MyShellRouteData extends ShellRouteData {
+  const MyShellRouteData();
+
+  static final List<NavigatorObserver> $observers = <NavigatorObserver>[
+    MyNavigatorObserver()
+  ];
+
+  @override
+  Widget builder(BuildContext context, GoRouterState state, Widget navigator) {
+    return MyShellRouteScreen(child: navigator);
+  }
+}
+
+class MyNavigatorObserver extends NavigatorObserver {
+  @override
+  void didPush(Route<dynamic> route, Route<dynamic>? previousRoute) {}
+}
+
+class MyShellRouteScreen extends StatelessWidget {
+  const MyShellRouteScreen({required this.child, super.key});
+
+  final Widget child;
+
+  int getCurrentIndex(BuildContext context) {
+    final String location = GoRouterState.of(context).uri.toString();
+    if (location.startsWith('/users')) {
+      return 1;
+    }
+    return 0;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final int selectedIndex = getCurrentIndex(context);
+
+    return Scaffold(
+      body: Row(
+        children: <Widget>[
+          NavigationRail(
+            destinations: const <NavigationRailDestination>[
+              NavigationRailDestination(
+                icon: Icon(Icons.home),
+                label: Text('Home'),
+              ),
+              NavigationRailDestination(
+                icon: Icon(Icons.group),
+                label: Text('Users'),
+              ),
+            ],
+            selectedIndex: selectedIndex,
+            onDestinationSelected: (int index) {
+              switch (index) {
+                case 0:
+                  const HomeRouteData().go(context);
+                  break;
+                case 1:
+                  const UsersRouteData().go(context);
+                  break;
+              }
+            },
+          ),
+          const VerticalDivider(thickness: 1, width: 1),
+          Expanded(child: child),
+        ],
+      ),
+    );
+  }
+}
+
+class HomeRouteData extends GoRouteData {
+  const HomeRouteData();
+
+  @override
+  Widget build(BuildContext context, GoRouterState state) {
+    return const Center(child: Text('The home page'));
+  }
+}
+
+class UsersRouteData extends GoRouteData {
+  const UsersRouteData();
+
+  @override
+  Widget build(BuildContext context, GoRouterState state) {
+    return ListView(
+      children: <Widget>[
+        for (int userID = 1; userID <= 3; userID++)
+          ListTile(
+            title: Text('User $userID'),
+            onTap: () => UserRouteData(id: userID).go(context),
+          ),
+      ],
+    );
+  }
+}
+
+class DialogPage extends Page<void> {
+  /// A page to display a dialog.
+  const DialogPage({required this.child, super.key});
+
+  /// The widget to be displayed which is usually a [Dialog] widget.
+  final Widget child;
+
+  @override
+  Route<void> createRoute(BuildContext context) {
+    return DialogRoute<void>(
+      context: context,
+      settings: this,
+      builder: (BuildContext context) => child,
+    );
+  }
+}
+
+class UserRouteData extends GoRouteData {
+  const UserRouteData({required this.id});
+
+  // Without this static key, the dialog will not cover the navigation rail.
+  final int id;
+
+  @override
+  Page<void> buildPage(BuildContext context, GoRouterState state) {
+    return DialogPage(
+      key: state.pageKey,
+      child: Center(
+        child: SizedBox(
+          width: 300,
+          height: 300,
+          child: Card(child: Center(child: Text('User $id'))),
+        ),
+      ),
+    );
+  }
+}

packages/go_router_builder/lib/src/route_config.dart

@@ -40,6 +40,7 @@ class ShellRouteConfig extends RouteBaseConfig {
     required this.navigatorKey,
     required this.parentNavigatorKey,
     required super.routeDataClass,
+    required this.observers,
     required super.parent,
   }) : super._();
 
@@ -49,6 +50,9 @@ class ShellRouteConfig extends RouteBaseConfig {
   /// The parent navigator key.
   final String? parentNavigatorKey;
 
+  /// The navigator observers.
+  final String? observers;
+
   @override
   Iterable<String> classDeclarations() {
     if (routeDataClass.unnamedConstructor == null) {
@@ -72,7 +76,8 @@ class ShellRouteConfig extends RouteBaseConfig {
   @override
   String get routeConstructorParameters =>
       '${navigatorKey == null ? '' : 'navigatorKey: $navigatorKey,'}'
-      '${parentNavigatorKey == null ? '' : 'parentNavigatorKey: $parentNavigatorKey,'}';
+      '${parentNavigatorKey == null ? '' : 'parentNavigatorKey: $parentNavigatorKey,'}'
+      '${observers == null ? '' : 'observers: $observers,'}';
 
   @override
   String get factorConstructorParameters =>
@@ -475,6 +480,10 @@ abstract class RouteBaseConfig {
             classElement,
             parameterName: r'$parentNavigatorKey',
           ),
+          observers: _generateParameterGetterCode(
+            classElement,
+            parameterName: r'$observers',
+          ),
         );
         break;
       case 'TypedStatefulShellRoute':
@@ -568,7 +577,9 @@ abstract class RouteBaseConfig {
           if (!element.isStatic || element.name != parameterName) {
             return false;
           }
-          if (parameterName.toLowerCase().contains('navigatorkey')) {
+          if (parameterName
+              .toLowerCase()
+              .contains(RegExp('navigatorKey | observers'))) {
             final DartType type = element.type;
             if (type is! ParameterizedType) {
               return false;
@@ -591,7 +602,6 @@ abstract class RouteBaseConfig {
     if (fieldDisplayName != null) {
       return '${classElement.name}.$fieldDisplayName';
     }
-
     final String? methodDisplayName = classElement.methods
         .where((MethodElement element) {
           return element.isStatic && element.name == parameterName;

packages/go_router_builder/pubspec.yaml

@@ -2,7 +2,7 @@ name: go_router_builder
 description: >-
   A builder that supports generated strongly-typed route helpers for
   package:go_router
-version: 2.3.4
+version: 2.4.0
 repository: https://github.com/flutter/packages/tree/main/packages/go_router_builder
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+go_router_builder%22