Deep Linking & URL Navigation
Learn how to handle deep links and URL-based navigation in Flutter apps so external links and the web URL bar can route users to the right screen.
Deep Linking & URL Navigation is a free Flutter Mobile Development lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Flutter Mobile Development learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Why Deep Linking Matters
Deep linking lets an external source — an email, a notification, or a browser URL — open a specific screen inside your app instead of the home page.
- Improves user experience for shared content
- Essential for marketing campaigns and notifications
- On Flutter web, it ties your app to the browser URL bar
You will use a URL-based router to make this work cleanly.
Two Kinds of Deep Links
There are two common forms:
- Custom scheme links like
myapp://product/42 - Universal / App Links using real
https://URLs
Universal links are preferred because they fall back to a website if the app is not installed.
Meet the Router API
Flutter's Router API (Navigator 2.0) maps URLs to screens. Packages like go_router wrap it in a friendly declarative API.
You define routes with path patterns, and the router parses incoming URLs for you.
final router = GoRouter(
routes: [
GoRoute(path: '/', builder: (c, s) => HomeScreen()),
GoRoute(path: '/product/:id', builder: (c, s) => ProductScreen(s.pathParameters['id']!)),
],
);Path Parameters
The :id segment is a path parameter. When a user opens /product/42, you read it with state.pathParameters['id'].
This is how a deep link carries data into your screen.
GoRoute(
path: '/product/:id',
builder: (context, state) {
final id = state.pathParameters['id'];
return ProductScreen(productId: id!);
},
);Query Parameters
For optional values use query parameters: /search?q=phones&sort=price.
Read them via state.uri.queryParameters.
GoRoute(
path: '/search',
builder: (context, state) {
final q = state.uri.queryParameters['q'] ?? '';
return SearchScreen(query: q);
},
);Wiring the Router In
Use MaterialApp.router instead of MaterialApp so the app delegates navigation to the router.
MaterialApp.router(
routerConfig: router,
title: 'My App',
);Navigating Programmatically
You can still navigate from code with context.go() (replace stack) or context.push() (add to stack).
ElevatedButton(
onPressed: () => context.go('/product/42'),
child: const Text('Open product'),
);Android Configuration
For real https App Links on Android, add an intent-filter with autoVerify to AndroidManifest.xml and host an assetlinks.json file on your domain.
<intent-filter android:autoVerify="true">
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="https" android:host="myapp.com" />
</intent-filter>iOS Configuration
On iOS, configure Associated Domains in Xcode with applinks:myapp.com and host an apple-app-site-association file at your domain root.
<!-- Associated Domains entitlement -->
applinks:myapp.comHandling Unknown Routes
Always provide an errorBuilder so a bad or unknown deep link shows a friendly 404 screen instead of crashing.
GoRouter(
routes: [...],
errorBuilder: (context, state) => const NotFoundScreen(),
);Redirects & Guards
Use the redirect callback to guard routes — for example send unauthenticated users from /profile to /login.
GoRouter(
redirect: (context, state) {
final loggedIn = auth.isLoggedIn;
if (!loggedIn && state.uri.path == '/profile') return '/login';
return null;
},
routes: [...],
);Quick Check
How do you read the value of id from a deep link matching /product/:id?
Recap
You learned how to add deep linking and URL navigation to a Flutter app:
- Custom scheme vs universal/App Links
- Path and query parameters with the Router API
- Native config on Android and iOS
- Error handling and route guards
Now external links and the browser URL bar can drive your app's navigation.
Frequently asked questions
Is the “Deep Linking & URL Navigation” lesson free?
Yes — the full text of “Deep Linking & URL Navigation” is free to read here on the web, and the Flutter Mobile Development course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Flutter Mobile Development course, upgrade to CoddyKit PRO.
What will I learn in “Deep Linking & URL Navigation”?
Learn how to handle deep links and URL-based navigation in Flutter apps so external links and the web URL bar can route users to the right screen. You practise Flutter Mobile Development with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Flutter Mobile Development?
No prior experience is required. Flutter Mobile Development on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Deep Linking & URL Navigation” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Flutter Mobile Development lesson?
Yes. Every Flutter Mobile Development lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Basic Page Navigation
- Named Routes & Arguments
- TabBars & Drawers
- Deep Linking & URL Navigation