Declarative Routing With go_router

Routes as configuration

For apps with many screens, web URLs or deep links, a declarative router maps paths to screens. go_router (a package maintained by the Flutter team) is the common choice: you declare GoRoutes with paths such as /products/:id, give the GoRouter to MaterialApp.router(routerConfig: ...), and navigate with context.go('/products/42') (replace the stack to match the URL) or context.push(...) (add on top). Nested routes build a back stack, ShellRoute and StatefulShellRoute keep a persistent bottom navigation bar, and a redirect callback can send unauthenticated users to a sign-in page. go_router's API has changed across major versions, so check the docs for your version.

A router with a path parameter

go_router configuration (API varies by version).

import 'package:go_router/go_router.dart';

final router = GoRouter(
  initialLocation: '/',
  redirect: (context, state) {
    final loggedIn = authService.isLoggedIn;
    final goingToLogin = state.matchedLocation == '/login';
    if (!loggedIn && !goingToLogin) return '/login';
    return null; // no redirect
  },
  routes: [
    GoRoute(path: '/login', builder: (context, state) => const LoginPage()),
    GoRoute(
      path: '/',
      builder: (context, state) => const HomePage(),
      routes: [
        GoRoute(
          path: 'products/:id', // child path: /products/42
          builder: (context, state) =>
              ProductPage(id: state.pathParameters['id']!),
        ),
      ],
    ),
  ],
);

// app root
MaterialApp.router(routerConfig: router);

// navigating
context.go('/products/42');

go versus push

context.go makes the stack match the URL, so going "back" follows the route hierarchy; context.push stacks a page on top of the current one. Mixing them carelessly produces surprising back-button behaviour.

Quick check: What is a main advantage of declarative routing with go_router?

• It replaces state management
• It removes the need for widgets
• It makes apps compile faster
• Screens are addressable by URL, which supports the web and deep links