feat(linux): migrate to xdg-desktop-portal for notifications

The xdg-desktop-portal is the new standard for desktop notifications
and is supported by GNOME, KDE, and other desktop environments. It
also works with Flatpak and Snap applications.

Resolves #1757

Author: Merrit

flutter_local_notifications/example/lib/main.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 import 'dart:io';
 // ignore: unnecessary_import
 import 'dart:typed_data';
+import 'dart:ui';
 
 import 'package:device_info_plus/device_info_plus.dart';
 import 'package:flutter/cupertino.dart';
@@ -12,7 +13,6 @@ import 'package:flutter/services.dart';
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:flutter_timezone/flutter_timezone.dart';
 import 'package:http/http.dart' as http;
-import 'package:image/image.dart' as image;
 import 'package:path_provider/path_provider.dart';
 import 'package:timezone/data/latest_all.dart' as tz;
 import 'package:timezone/timezone.dart' as tz;
@@ -52,10 +52,10 @@ class ReceivedNotification {
 String? selectedNotificationPayload;
 
 /// A notification action which triggers a url launch event
-const String urlLaunchActionId = 'id_1';
+const String urlLaunchActionId = 'id1';
 
 /// A notification action which triggers a App navigation event
-const String navigationActionId = 'id_3';
+const String navigationActionId = 'id3';
 
 /// Defines a iOS/MacOS notification category for text input actions.
 const String darwinNotificationCategoryText = 'textCategory';
@@ -1153,8 +1153,12 @@ class _HomePageState extends State<HomePage> {
       linux: linuxNotificationDetails,
     );
     await flutterLocalNotificationsPlugin.show(
-        id++, 'plain title', 'plain body', notificationDetails,
-        payload: 'item z');
+      id++,
+      'plain title',
+      'plain body',
+      notificationDetails,
+      payload: 'item z',
+    );
   }
 
   Future<void> _showNotificationWithTextAction() async {
@@ -2831,17 +2835,20 @@ Future<void> _showLinuxNotificationWithByteDataIcon() async {
   final ByteData assetIcon = await rootBundle.load(
     'icons/app_icon_density.png',
   );
-  final image.Image? iconData = image.decodePng(
-    assetIcon.buffer.asUint8List().toList(),
-  );
-  final Uint8List iconBytes = iconData!.getBytes();
+
+  final Uint8List iconBytes = assetIcon.buffer.asUint8List();
+  final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(iconBytes);
+  final ImageDescriptor descriptor = await ImageDescriptor.encoded(buffer);
+  final int width = descriptor.width;
+  final int height = descriptor.height;
+
   final LinuxNotificationDetails linuxPlatformChannelSpecifics =
       LinuxNotificationDetails(
     icon: ByteDataLinuxIcon(
       LinuxRawIconData(
         data: iconBytes,
-        width: iconData.width,
-        height: iconData.height,
+        width: width,
+        height: height,
         channels: 4, // The icon has an alpha channel
         hasAlpha: true,
       ),

flutter_local_notifications/pubspec.yaml

@@ -14,6 +14,10 @@ dependencies:
   flutter_local_notifications_platform_interface: ^7.0.0
   timezone: ^0.9.0
 
+dependency_overrides:
+  flutter_local_notifications_linux:
+    path: ../flutter_local_notifications_linux
+
 dev_dependencies:
   flutter_driver:
     sdk: flutter

flutter_local_notifications_linux/assets/icons/app_icon.png

@@ -1,7 +1,7 @@
 /// The Linux implementation of `flutter_local_notifications`.
 library flutter_local_notifications_linux;
 
-// flutter_local_notifications_linux depends on dbus and posix
+// flutter_local_notifications_linux depends on posix
 // which uses FFI internally; export a stub for platforms that don't
 // support FFI (e.g., web) to avoid having transitive dependencies
 // break web compilation.

flutter_local_notifications_linux/lib/flutter_local_notifications_linux.dart

@@ -77,14 +77,4 @@ class LinuxFlutterLocalNotificationsPlugin
   @override
   Future<LinuxServerCapabilities> getCapabilities() =>
       _manager.getCapabilities();
-
-  /// Returns a [Map] with the specified notification id as the key
-  /// and the id, assigned by the system, as the value.
-  ///
-  /// Note: the system ID is unique only within the current user session,
-  /// so it's undesirable to save it to persistable storage without any
-  /// invalidation/update. For more information, please see
-  /// Desktop Notifications Specification https://specifications.freedesktop.org/notification-spec/latest/ar01s02.html
-  @override
-  Future<Map<int, int>> getSystemIdMap() => _manager.getSystemIdMap();
 }

flutter_local_notifications_linux/lib/src/dbus_wrapper.dart

@@ -36,13 +36,4 @@ abstract class FlutterLocalNotificationsPlatformLinux
   /// Some functionality may not be implemented by the notification server,
   /// conforming clients should check if it is available before using it.
   Future<LinuxServerCapabilities> getCapabilities();
-
-  /// Returns a [Map] with the specified notification id as the key
-  /// and the id, assigned by the system, as the value.
-  ///
-  /// Note: the system ID is unique only within the current user session,
-  /// so it's undesirable to save it to persistable storage without any
-  /// invalidation/update. For more information, please see
-  /// Desktop Notifications Specification https://specifications.freedesktop.org/notification-spec/latest/ar01s02.html
-  Future<Map<int, int>> getSystemIdMap();
 }

flutter_local_notifications_linux/lib/src/flutter_local_notifications.dart

@@ -49,12 +49,4 @@ class LinuxFlutterLocalNotificationsPlugin
     assert(false);
     throw UnimplementedError();
   }
-
-  /// Errors on attempted calling of the stub. It exists only to satisfy
-  /// compile-time dependencies, and should never actually be called.
-  @override
-  Future<Map<int, int>> getSystemIdMap() async {
-    assert(false);
-    throw UnimplementedError();
-  }
 }

flutter_local_notifications_linux/lib/src/flutter_local_notifications_platform_linux.dart

@@ -6,7 +6,6 @@ class LinuxNotificationInfo {
   /// Constructs an instance of [LinuxPlatformInfoData].
   const LinuxNotificationInfo({
     required this.id,
-    required this.systemId,
     this.payload,
     this.actions = const <LinuxNotificationActionInfo>[],
   });
@@ -21,7 +20,6 @@ class LinuxNotificationInfo {
         .toList();
     return LinuxNotificationInfo(
       id: json['id'] as int,
-      systemId: json['systemId'] as int,
       payload: json['payload'] as String?,
       actions: actions ?? <LinuxNotificationActionInfo>[],
     );
@@ -30,10 +28,6 @@ class LinuxNotificationInfo {
   /// Notification id
   final int id;
 
-  /// Notification id, which is returned by the system,
-  /// see Desktop Notifications Specification https://specifications.freedesktop.org/notification-spec/latest/
-  final int systemId;
-
   /// Notification payload, that will be passed back to the app
   /// when a notification is tapped on.
   final String? payload;
@@ -44,7 +38,6 @@ class LinuxNotificationInfo {
   /// Returns the object as a key-value map
   Map<String, dynamic> toJson() => <String, dynamic>{
         'id': id,
-        'systemId': systemId,
         'payload': payload,
         'actions':
             actions.map((LinuxNotificationActionInfo a) => a.toJson()).toList(),
@@ -60,7 +53,6 @@ class LinuxNotificationInfo {
   }) =>
       LinuxNotificationInfo(
         id: id ?? this.id,
-        systemId: systemId ?? this.systemId,
         payload: payload ?? this.payload,
         actions: actions ?? this.actions,
       );
@@ -73,14 +65,12 @@ class LinuxNotificationInfo {
 
     return other is LinuxNotificationInfo &&
         other.id == id &&
-        other.systemId == systemId &&
         other.payload == payload &&
         listEquals(other.actions, actions);
   }
 
   @override
-  int get hashCode =>
-      id.hashCode ^ systemId.hashCode ^ payload.hashCode ^ actions.hashCode;
+  int get hashCode => id.hashCode ^ payload.hashCode ^ actions.hashCode;
 }
 
 /// Represents a Linux notification action information