Use functions instead of classes for notification will display listeners

Author: emawby

example/lib/main.dart

@@ -11,10 +11,7 @@ class MyApp extends StatefulWidget {
   _MyAppState createState() => new _MyAppState();
 }
 
-class _MyAppState extends State<MyApp>
-    with
-        OneSignalNotificationLifecycleListener,
-        OneSignalNotificationClickListener {
+class _MyAppState extends State<MyApp> with OneSignalNotificationClickListener {
   String _debugLabelString = "";
   String? _emailAddress;
   String? _smsNumber;
@@ -61,7 +58,25 @@ class _MyAppState extends State<MyApp>
     });
 
     OneSignal.Notifications.addClickListener(this);
-    OneSignal.Notifications.addLifecycleListener(this);
+
+    OneSignal.Notifications.addForegroundWillDisplayListener((event) {
+      print(
+          'NOTIFICATION WILL DISPLAY LISTENER CALLED WITH: ${event.notification.jsonRepresentation()}');
+
+      /// Display Notification, preventDefault to not display
+      event.preventDefault();
+
+      /// Do async work
+
+      /// notification.display() to display after preventing default
+      event.notification.display();
+
+      this.setState(() {
+        _debugLabelString =
+            "Notification received in foreground notification: \n${event.notification.jsonRepresentation().replaceAll("\\n", "\n")}";
+      });
+    });
+
     OneSignal.InAppMessages.addClickListener((event) {
       this.setState(() {
         _debugLabelString =
@@ -94,7 +109,7 @@ class _MyAppState extends State<MyApp>
     // Some examples of how to use Outcome Events public methods with OneSignal SDK
     oneSignalOutcomeExamples();
 
-    OneSignal.InAppMessages.paused(false);
+    OneSignal.InAppMessages.paused(true);
   }
 
   void onClickNotification(OSNotificationClickEvent event) {
@@ -105,24 +120,6 @@ class _MyAppState extends State<MyApp>
     });
   }
 
-  void onWillDisplayNotification(OSNotificationWillDisplayEvent event) {
-    print(
-        'NOTIFICATION WILL DISPLAY LISTENER CALLED WITH: ${event.notification.jsonRepresentation()}');
-
-    /// Display Notification, preventDefault to not display
-    event.preventDefault();
-
-    /// Do async work
-
-    /// notification.display() to display after preventing default
-    event.notification.display();
-
-    this.setState(() {
-      _debugLabelString =
-          "Notification received in foreground notification: \n${event.notification.jsonRepresentation().replaceAll("\\n", "\n")}";
-    });
-  }
-
   void _handleSendTags() {
     print("Sending tags");
     OneSignal.User.addTagWithKey("test2", "val2");

lib/src/notifications.dart

@@ -7,9 +7,8 @@ import 'package:onesignal_flutter/src/permission.dart';
 
 typedef void OnNotificationPermissionChangeObserver(bool permission);
 
-class OneSignalNotificationLifecycleListener {
-  void onWillDisplayNotification(OSNotificationWillDisplayEvent event) {}
-}
+typedef void OnNotificationWillDisplayListener(
+    OSNotificationWillDisplayEvent event);
 
 class OneSignalNotificationClickListener {
   void onClickNotification(OSNotificationClickEvent event) {}
@@ -19,8 +18,8 @@ class OneSignalNotifications {
   // event listeners
   List<OneSignalNotificationClickListener> _clickListeners =
       <OneSignalNotificationClickListener>[];
-  List<OneSignalNotificationLifecycleListener> _lifecycleListeners =
-      <OneSignalNotificationLifecycleListener>[];
+  List<OnNotificationWillDisplayListener> _willDisplayListeners =
+      <OnNotificationWillDisplayListener>[];
 
   // private channels used to bridge to ObjC/Java
   MethodChannel _channel = const MethodChannel('OneSignal#notifications');
@@ -132,8 +131,8 @@ class OneSignalNotifications {
             OSNotificationClickEvent(call.arguments.cast<String, dynamic>()));
       }
     } else if (call.method == 'OneSignal#onWillDisplayNotification') {
-      for (var listener in _lifecycleListeners) {
-        listener.onWillDisplayNotification(OSNotificationWillDisplayEvent(
+      for (var listener in _willDisplayListeners) {
+        listener(OSNotificationWillDisplayEvent(
             call.arguments.cast<String, dynamic>()));
       }
       var event = OSNotificationWillDisplayEvent(
@@ -152,13 +151,14 @@ class OneSignalNotifications {
     }
   }
 
-  void addLifecycleListener(OneSignalNotificationLifecycleListener listener) {
-    _lifecycleListeners.add(listener);
+  void addForegroundWillDisplayListener(
+      OnNotificationWillDisplayListener listener) {
+    _willDisplayListeners.add(listener);
   }
 
-  void removeLifecycleListener(
-      OneSignalNotificationLifecycleListener listener) {
-    _lifecycleListeners.remove(listener);
+  void removeForegroundWillDisplayListener(
+      OnNotificationWillDisplayListener listener) {
+    _willDisplayListeners.remove(listener);
   }
 
   /// The notification willDisplay listener is called whenever a notification arrives