setOnBackgroundMessage() is now a Future<void> that will await for the function to complete.

example/pubspec.lock

@@ -28,10 +28,10 @@ packages:
     dependency: transitive
     description:
       name: characters
-      sha256: e6a326c8af69605aec75ed6c187d06b349707a27fbff8222ca9cc2cff167975c
+      sha256: "04a925763edad70e8443c99234dc3328f442e811f1d8fd1a72f1c8ad0f69a605"
       url: "https://pub.dev"
     source: hosted
-    version: "1.2.1"
+    version: "1.3.0"
   charcode:
     dependency: transitive
     description:
@@ -52,10 +52,10 @@ packages:
     dependency: transitive
     description:
       name: collection
-      sha256: cfc915e6923fe5ce6e153b0723c753045de46de1b4d63771530504004a45fae0
+      sha256: f092b211a4319e98e5ff58223576de6c2803db36221657b46c82574721240687
       url: "https://pub.dev"
     source: hosted
-    version: "1.17.0"
+    version: "1.17.2"
   crypto:
     dependency: "direct main"
     description:
@@ -218,14 +218,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "4.0.0"
-  js:
-    dependency: transitive
-    description:
-      name: js
-      sha256: "5528c2f391ededb7775ec1daa69e65a2d61276f7552de2b5f7b8d34ee9fd4ab7"
-      url: "https://pub.dev"
-    source: hosted
-    version: "0.6.5"
   lints:
     dependency: transitive
     description:
@@ -238,18 +230,18 @@ packages:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: d92141dc6fe1dad30722f9aa826c7fbc896d021d792f80678280601aff8cf724
+      sha256: "9528f2f296073ff54cb9fee677df673ace1218163c3bc7628093e7eed5203d41"
       url: "https://pub.dev"
     source: hosted
-    version: "0.2.0"
+    version: "0.5.0"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: "6c268b42ed578a53088d834796959e4a1814b5e9e164f147f580a386e5decf42"
+      sha256: "3c74dbf8763d36539f114c799d8a2d87343b5067e9d796ca22b5eb8437090ee3"
       url: "https://pub.dev"
     source: hosted
-    version: "1.8.0"
+    version: "1.9.1"
   path:
     dependency: transitive
     description:
@@ -367,6 +359,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.4"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: dc8ccd225a2005c1be616fe02951e2e342092edf968cf0844220383757ef8f10
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.1.4-beta"
   win32:
     dependency: transitive
     description:
@@ -392,5 +392,5 @@ packages:
     source: hosted
     version: "5.3.1"
 sdks:
-  dart: ">=2.17.0-0 <3.0.0"
+  dart: ">=3.1.0-185.0.dev <4.0.0"
   flutter: ">=2.8.0"

lib/src/platform/src/method_call_handler.dart

@@ -26,16 +26,13 @@ class AblyMethodCallHandler {
         case PlatformMethod.pushOnBackgroundMessage:
           return _onPushBackgroundMessage(call.arguments as RemoteMessage);
         case PlatformMethod.pushOnShowNotificationInForeground:
-          return _pushNotificationEvents
-              .showNotificationInForeground(call.arguments as RemoteMessage);
+          return _pushNotificationEvents.showNotificationInForeground(call.arguments as RemoteMessage);
         case PlatformMethod.pushOnNotificationTap:
           return _onNotificationTap(call.arguments as RemoteMessage);
         case PlatformMethod.pushOpenSettingsFor:
           return _onOpenSettingsFor();
         default:
-          throw PlatformException(
-              code: 'Received invalid method channel call from Platform side',
-              message: 'No such method ${call.method}');
+          throw PlatformException(code: 'Received invalid method channel call from Platform side', message: 'No such method ${call.method}');
       }
     });
   }
@@ -68,10 +65,8 @@ class AblyMethodCallHandler {
     return realtime.options.authCallback!(tokenParams);
   }
 
-  final PushActivationEventsInternal _pushActivationEvents =
-      Push.activationEvents as PushActivationEventsInternal;
-  final PushNotificationEventsInternal _pushNotificationEvents =
-      Push.notificationEvents as PushNotificationEventsInternal;
+  final PushActivationEventsInternal _pushActivationEvents = Push.activationEvents as PushActivationEventsInternal;
+  final PushNotificationEventsInternal _pushNotificationEvents = Push.notificationEvents as PushNotificationEventsInternal;
 
   Future<Object?> _onPushOnActivate(ErrorInfo? error) async {
     _pushActivationEvents.onActivateStreamController.add(error);
@@ -94,13 +89,12 @@ class AblyMethodCallHandler {
   }
 
   Future<Object?> _onPushBackgroundMessage(RemoteMessage remoteMessage) async {
-    _pushNotificationEvents.handleBackgroundMessage(remoteMessage);
+    await _pushNotificationEvents.handleBackgroundMessage(remoteMessage);
     return null;
   }
 
   Future<Object?> _onNotificationTap(RemoteMessage remoteMessage) async {
-    _pushNotificationEvents.onNotificationTapStreamController
-        .add(remoteMessage);
+    _pushNotificationEvents.onNotificationTapStreamController.add(remoteMessage);
     return null;
   }
 

lib/src/platform/src/push_notification_events_internal.dart

@@ -14,43 +14,36 @@ class PushNotificationEventsInternal implements PushNotificationEvents {
 
   /// @nodoc
   /// Invoked when pushOnShowNotificationInForeground platform method is called.
-  Future<bool> Function(RemoteMessage message)?
-      onShowNotificationInForegroundHandler;
+  Future<bool> Function(RemoteMessage message)? onShowNotificationInForegroundHandler;
 
   /// @nodoc
   /// Exposes stream of received [RemoteMessage] objects.
   ///
   /// New message is emitted after pushOnMessage platform method is called
-  StreamController<RemoteMessage> onMessageStreamController =
-      StreamController();
+  StreamController<RemoteMessage> onMessageStreamController = StreamController();
 
   /// @nodoc
   /// Controller used to indicate notification was tapped.
-  StreamController<RemoteMessage> onNotificationTapStreamController =
-      StreamController();
+  StreamController<RemoteMessage> onNotificationTapStreamController = StreamController();
 
   BackgroundMessageHandler? _onBackgroundMessage;
 
   @override
-  Future<RemoteMessage?> get notificationTapLaunchedAppFromTerminated =>
-      Platform().invokePlatformMethod<RemoteMessage>(
-          PlatformMethod.pushNotificationTapLaunchedAppFromTerminated);
+  Future<RemoteMessage?> get notificationTapLaunchedAppFromTerminated => Platform().invokePlatformMethod<RemoteMessage>(PlatformMethod.pushNotificationTapLaunchedAppFromTerminated);
 
   @override
   Stream<RemoteMessage> get onMessage => onMessageStreamController.stream;
 
   @override
-  Stream<RemoteMessage> get onNotificationTap =>
-      onNotificationTapStreamController.stream;
+  Stream<RemoteMessage> get onNotificationTap => onNotificationTapStreamController.stream;
 
   @override
   void setOnOpenSettings(VoidCallback callback) {
     onOpenSettingsHandler = callback;
   }
 
   @override
-  void setOnShowNotificationInForeground(
-      Future<bool> Function(RemoteMessage message) callback) {
+  void setOnShowNotificationInForeground(Future<bool> Function(RemoteMessage message) callback) {
     onShowNotificationInForegroundHandler = callback;
   }
 
@@ -81,9 +74,13 @@ class PushNotificationEventsInternal implements PushNotificationEvents {
 
   /// @nodoc
   /// Handles a RemoteMessage passed from the platform side.
-  void handleBackgroundMessage(RemoteMessage remoteMessage) {
+  Future<void> handleBackgroundMessage(RemoteMessage remoteMessage) async {
     if (_onBackgroundMessage != null) {
-      _onBackgroundMessage!(remoteMessage);
+      final onBackgroundMessageResult = _onBackgroundMessage!(remoteMessage);
+      // ^^^ _onBackgroundMessage() can return void or Future<void>
+      if (onBackgroundMessageResult is Future) {
+        await onBackgroundMessageResult; // if it returns a Future we await on it.
+      }
     } else {
       // ignore:avoid_print
       print('Received RemoteMessage but no handler was set. '

lib/src/push_notifications/src/push_notification_events.dart

@@ -4,7 +4,7 @@ import 'package:ably_flutter/ably_flutter.dart';
 
 /// Type definition for a callback invoked when background push message
 /// is received.
-typedef BackgroundMessageHandler = void Function(RemoteMessage message);
+typedef BackgroundMessageHandler = dynamic Function(RemoteMessage message);
 
 /// Push Notification events, such as message arriving or notification tap.
 abstract class PushNotificationEvents {

pubspec.lock

@@ -5,10 +5,10 @@ packages:
     dependency: transitive
     description:
       name: async
-      sha256: bfe67ef28df125b7dddcea62755991f807aa39a2492a23e1550161692950bbe0
+      sha256: "947bfcf187f74dbc5e146c9eb9c0f10c9f8b30743e341481c1e2ed3ecc18c20c"
       url: "https://pub.dev"
     source: hosted
-    version: "2.10.0"
+    version: "2.11.0"
   boolean_selector:
     dependency: transitive
     description:
@@ -21,10 +21,10 @@ packages:
     dependency: transitive
     description:
       name: characters
-      sha256: e6a326c8af69605aec75ed6c187d06b349707a27fbff8222ca9cc2cff167975c
+      sha256: "04a925763edad70e8443c99234dc3328f442e811f1d8fd1a72f1c8ad0f69a605"
       url: "https://pub.dev"
     source: hosted
-    version: "1.2.1"
+    version: "1.3.0"
   clock:
     dependency: transitive
     description:
@@ -37,10 +37,10 @@ packages:
     dependency: "direct main"
     description:
       name: collection
-      sha256: cfc915e6923fe5ce6e153b0723c753045de46de1b4d63771530504004a45fae0
+      sha256: f092b211a4319e98e5ff58223576de6c2803db36221657b46c82574721240687
       url: "https://pub.dev"
     source: hosted
-    version: "1.17.0"
+    version: "1.17.2"
   fake_async:
     dependency: "direct dev"
     description:
@@ -67,14 +67,6 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
-  js:
-    dependency: transitive
-    description:
-      name: js
-      sha256: "5528c2f391ededb7775ec1daa69e65a2d61276f7552de2b5f7b8d34ee9fd4ab7"
-      url: "https://pub.dev"
-    source: hosted
-    version: "0.6.5"
   lints:
     dependency: transitive
     description:
@@ -87,34 +79,34 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: "16db949ceee371e9b99d22f88fa3a73c4e59fd0afed0bd25fc336eb76c198b72"
+      sha256: "1803e76e6653768d64ed8ff2e1e67bea3ad4b923eb5c56a295c3e634bad5960e"
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.13"
+    version: "0.12.16"
   material_color_utilities:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: d92141dc6fe1dad30722f9aa826c7fbc896d021d792f80678280601aff8cf724
+      sha256: "9528f2f296073ff54cb9fee677df673ace1218163c3bc7628093e7eed5203d41"
       url: "https://pub.dev"
     source: hosted
-    version: "0.2.0"
+    version: "0.5.0"
   meta:
     dependency: "direct main"
     description:
       name: meta
-      sha256: "6c268b42ed578a53088d834796959e4a1814b5e9e164f147f580a386e5decf42"
+      sha256: "3c74dbf8763d36539f114c799d8a2d87343b5067e9d796ca22b5eb8437090ee3"
       url: "https://pub.dev"
     source: hosted
-    version: "1.8.0"
+    version: "1.9.1"
   path:
     dependency: transitive
     description:
       name: path
-      sha256: db9d4f58c908a4ba5953fcee2ae317c94889433e5024c27ce74a37f94267945b
+      sha256: "8829d8a55c13fc0e37127c29fedf290c102f4e40ae94ada574091fe0ff96c917"
       url: "https://pub.dev"
     source: hosted
-    version: "1.8.2"
+    version: "1.8.3"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -124,10 +116,10 @@ packages:
     dependency: transitive
     description:
       name: source_span
-      sha256: dd904f795d4b4f3b870833847c461801f6750a9fa8e61ea5ac53f9422b31f250
+      sha256: "53e943d4206a5e30df338fd4c6e7a077e02254531b138a15aec3bd143c1a8b3c"
       url: "https://pub.dev"
     source: hosted
-    version: "1.9.1"
+    version: "1.10.0"
   stack_trace:
     dependency: transitive
     description:
@@ -164,10 +156,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: ad540f65f92caa91bf21dfc8ffb8c589d6e4dc0c2267818b4cc2792857706206
+      sha256: "75760ffd7786fffdfb9597c35c5b27eaeec82be8edfb6d71d32651128ed7aab8"
       url: "https://pub.dev"
     source: hosted
-    version: "0.4.16"
+    version: "0.6.0"
   vector_math:
     dependency: transitive
     description:
@@ -176,6 +168,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.4"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: dc8ccd225a2005c1be616fe02951e2e342092edf968cf0844220383757ef8f10
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.1.4-beta"
 sdks:
-  dart: ">=2.18.0 <3.0.0"
+  dart: ">=3.1.0-185.0.dev <4.0.0"
   flutter: ">=2.5.0"