Deep linking is a mechanism for launching an app with a URI. This URI contains scheme, host, and path, and opens the app to a specific screen.

Anapp link is a type of deep link that useshttp orhttps and is exclusive to Android devices.

Setting up app links requires one to own a web domain. Otherwise, consider usingFirebase Hosting orGitHub Pages as a temporary solution.

Once you've set up your deep links, you can validate them. To learn more, seeValidate deep links.

Write a Flutter app that can handle an incoming URL. This example uses thego_router package to handle the routing. The Flutter team maintains thego_router package. It provides a simple API to handle complex routing scenarios.

1. To create a new application, typeflutter create <app-name>:

   $flutter create deeplink_cookbook

   content_copy

2. To includego_router package in your app, add a dependency forgo_router to the project:

   To add thego_router package as a dependency, runflutter pub add:

   $flutter pub add go_router

   content_copy

3. To handle the routing, create aGoRouter object in themain.dart file:

   main.dart

   dart

   import'package:flutter/material.dart';import'package:go_router/go_router.dart';​voidmain()=>runApp(MaterialApp.router(routerConfig:router));​/// This handles '/' and '/details'.finalrouter=GoRouter(routes:[GoRoute(path:'/',builder:(_,_)=>Scaffold(appBar:AppBar(title:constText('Home Screen')),),routes:[GoRoute(path:'details',builder:(_,_)=>Scaffold(appBar:AppBar(title:constText('Details Screen')),),),],),],);

   content_copy

1. Open the Flutter project with VS Code or Android Studio.

2. Navigate toandroid/app/src/main/AndroidManifest.xml file.

3. Add the following metadata tag and intent filter inside the<activity> tag with.MainActivity.

   Replaceexample.com with your own web domain.

   xml

   <intent-filter android:autoVerify="true"><action android:name="android.intent.action.VIEW" /><category android:name="android.intent.category.DEFAULT" /><category android:name="android.intent.category.BROWSABLE" /><data android:scheme="http" android:host="example.com" /><data android:scheme="https" /></intent-filter>

   content_copy
   merge_typeVersion note

   If you use a Flutter version earlier than 3.27, you need to manually opt in to deep linking by adding the following metadata tag to<activity>:

   xml

   <meta-data android:name="flutter_deeplinking_enabled" android:value="true" />

   content_copy
   infoNote

   If you use a third-party plugin to handle deep links, such asapp_links, Flutter's default deeplink handler will break these plugins.

   To opt out of using Flutter's default deep link handler, add the following metadata tag to<activity>:

   xml

   <meta-data android:name="flutter_deeplinking_enabled" android:value="false" />

   content_copy

Host anassetlinks.json file in using a web server with a domain that you own. This file tells the mobile browser which Android application to open instead of the browser. To create the file, get the package name of the Flutter app you created in the previous step and the sha256 fingerprint of the signing key you will be using to build the APK.

Locate the package name inAndroidManifest.xml, thepackage property under<manifest> tag. Package names are usually in the format ofcom.example.*.

The process might differ depending on how the apk is signed.

You can find the sha256 fingerprint directly from play developer console. Open your app in the play console, underRelease> Setup > App Integrity> App Signing tab:

If you are storing the key locally, you can generate sha256 using the following command:

keytool -list -v -keystore <path-to-keystore>

The hosted file should look similar to this:

[{"relation":["delegate_permission/common.handle_all_urls"],"target":{"namespace":"android_app","package_name":"com.example.deeplink_cookbook","sha256_cert_fingerprints":["FF:2A:CF:7B:DD:CC:F1:03:3E:E8:B2:27:7C:A2:E3:3C:DE:13:DB:AC:8E:EB:3A:B9:72:A1:0E:26:8A:F5:EC:AF"]}}]

1. Set thepackage_name value to your Android application ID.

2. Set sha256_cert_fingerprints to the value you got from the previous step.

3. Host the file at a URL that resembles the following:<webdomain>/.well-known/assetlinks.json

4. Verify that your browser can access this file.

You can use a real device or the Emulator to test an app link, but first make sure you have executedflutter run at least once on the devices. This ensures that the Flutter application is installed.

To testonly the app setup, use the adb command:

adb shell 'am start -a android.intent.action.VIEW \    -c android.intent.category.BROWSABLE \    -d "http://<web-domain>/details"' \    <package name>

infoNote

If you are debugging locally (and not downloading the app from the Play Store), you might need to enable the toggle forSupported web addresses manually.

If everything is set up correctly, the Flutter application launches and displays the details screen:

Source code:deeplink_cookbook