implement open in app feature

packages/flutter_mozilla_components/lib/flutter_mozilla_components.dart

@@ -8,6 +8,7 @@ export 'src/data/models/load_url_flags.dart';
 export 'src/data/models/source.dart';
 export 'src/domain/entities/default_selection_actions.dart';
 export 'src/domain/services/gecko_addon.dart';
+export 'src/domain/services/gecko_app_links.dart';
 export 'src/domain/services/gecko_bookmarks.dart';
 export 'src/domain/services/gecko_browser.dart';
 export 'src/domain/services/gecko_browser_extension.dart';

packages/flutter_mozilla_components/lib/src/domain/services/gecko_app_links.dart

@@ -0,0 +1,40 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+import 'package:flutter_mozilla_components/src/pigeons/gecko.g.dart';
+
+final _api = GeckoAppLinksApi();
+
+/// Service for detecting and launching external applications that can handle URLs.
+///
+/// This service wraps Mozilla Android Components' AppLinksUseCases to allow
+/// checking if native apps can handle URLs and launching them directly.
+/// This matches the behavior in Firefox/Fenix for "Open in App" functionality.
+class GeckoAppLinksService {
+  /// Checks if an external application is available to handle the given URL.
+  ///
+  /// This method uses mozilla-components AppLinksUseCases to determine if
+  /// a native app can handle the URL (e.g., YouTube app for youtube.com links).
+  ///
+  /// @param url The URL to check.
+  /// @return true if an external app is available, false otherwise.
+  Future<bool> hasExternalApp(Uri url) {
+    return _api.hasExternalApp(url.toString());
+  }
+
+  /// Opens the URL in an external application if available.
+  ///
+  /// This method will:
+  /// 1. Check if an external app can handle the URL
+  /// 2. If available, launch the app directly with Intent.FLAG_ACTIVITY_NEW_TASK
+  /// 3. Return true if successfully launched, false otherwise
+  ///
+  /// @param url The URL to open in external app.
+  /// @return true if URL was opened in external app, false if no app available.
+  Future<bool> openAppLink(Uri url) {
+    return _api.openAppLink(url.toString());
+  }
+}

packages/flutter_mozilla_components/lib/src/pigeons/gecko.g.dart

@@ -8272,3 +8272,89 @@ class GeckoTrackingProtectionApi {
     }
   }
 }
+
+/// API for detecting and launching external applications that can handle URLs.
+///
+/// This API wraps Mozilla Android Components' AppLinksUseCases to allow Flutter
+/// code to check if native apps can handle URLs and launch them directly.
+class GeckoAppLinksApi {
+  /// Constructor for [GeckoAppLinksApi].  The [binaryMessenger] named argument is
+  /// available for dependency injection.  If it is left null, the default
+  /// BinaryMessenger will be used which routes to the host platform.
+  GeckoAppLinksApi({BinaryMessenger? binaryMessenger, String messageChannelSuffix = ''})
+      : pigeonVar_binaryMessenger = binaryMessenger,
+        pigeonVar_messageChannelSuffix = messageChannelSuffix.isNotEmpty ? '.$messageChannelSuffix' : '';
+  final BinaryMessenger? pigeonVar_binaryMessenger;
+
+  static const MessageCodec<Object?> pigeonChannelCodec = _PigeonCodec();
+
+  final String pigeonVar_messageChannelSuffix;
+
+  /// Checks if an external application is available to handle the given URL.
+  ///
+  /// This method uses mozilla-components AppLinksUseCases to determine if
+  /// a native app can handle the URL (e.g., YouTube app for youtube.com links).
+  ///
+  /// Returns true if an external app is available, false otherwise.
+  Future<bool> hasExternalApp(String url) async {
+    final pigeonVar_channelName = 'dev.flutter.pigeon.flutter_mozilla_components.GeckoAppLinksApi.hasExternalApp$pigeonVar_messageChannelSuffix';
+    final pigeonVar_channel = BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final Future<Object?> pigeonVar_sendFuture = pigeonVar_channel.send(<Object?>[url]);
+    final pigeonVar_replyList = await pigeonVar_sendFuture as List<Object?>?;
+    if (pigeonVar_replyList == null) {
+      throw _createConnectionError(pigeonVar_channelName);
+    } else if (pigeonVar_replyList.length > 1) {
+      throw PlatformException(
+        code: pigeonVar_replyList[0]! as String,
+        message: pigeonVar_replyList[1] as String?,
+        details: pigeonVar_replyList[2],
+      );
+    } else if (pigeonVar_replyList[0] == null) {
+      throw PlatformException(
+        code: 'null-error',
+        message: 'Host platform returned null value for non-null return value.',
+      );
+    } else {
+      return (pigeonVar_replyList[0] as bool?)!;
+    }
+  }
+
+  /// Opens the URL in an external application if available.
+  ///
+  /// This method will:
+  /// 1. Check if an external app can handle the URL
+  /// 2. If available, launch the app directly with Intent.FLAG_ACTIVITY_NEW_TASK
+  /// 3. Return true if successfully launched, false otherwise
+  ///
+  /// Returns true if URL was opened in external app, false if no app available.
+  Future<bool> openAppLink(String url) async {
+    final pigeonVar_channelName = 'dev.flutter.pigeon.flutter_mozilla_components.GeckoAppLinksApi.openAppLink$pigeonVar_messageChannelSuffix';
+    final pigeonVar_channel = BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final Future<Object?> pigeonVar_sendFuture = pigeonVar_channel.send(<Object?>[url]);
+    final pigeonVar_replyList = await pigeonVar_sendFuture as List<Object?>?;
+    if (pigeonVar_replyList == null) {
+      throw _createConnectionError(pigeonVar_channelName);
+    } else if (pigeonVar_replyList.length > 1) {
+      throw PlatformException(
+        code: pigeonVar_replyList[0]! as String,
+        message: pigeonVar_replyList[1] as String?,
+        details: pigeonVar_replyList[2],
+      );
+    } else if (pigeonVar_replyList[0] == null) {
+      throw PlatformException(
+        code: 'null-error',
+        message: 'Host platform returned null value for non-null return value.',
+      );
+    } else {
+      return (pigeonVar_replyList[0] as bool?)!;
+    }
+  }
+}