Migrate to Flutter 2

* Add Null safety support

Author: Jeasmine

android/src/main/java/com/onesignal/flutter/OneSignalSerializer.java

@@ -59,6 +59,9 @@ private static HashMap<String, Object> convertEmailSubscriptionStateToMap(OSEmai
     static HashMap<String, Object> convertDeviceStateToMap(OSDeviceState state) {
         HashMap<String, Object> hash = new HashMap<>();
 
+        if (state == null)
+            return hash;
+
         hash.put("hasNotificationPermission", state.areNotificationsEnabled());
         hash.put("pushDisabled", state.isPushDisabled());
         hash.put("subscribed", state.isSubscribed());

example/lib/main.dart

@@ -13,8 +13,8 @@ class MyApp extends StatefulWidget {
 
 class _MyAppState extends State<MyApp> {
   String _debugLabelString = "";
-  String _emailAddress;
-  String _externalUserId;
+  String? _emailAddress;
+  String? _externalUserId;
   bool _enableConsentButton = false;
 
   // CHANGE THIS parameter to true if you want to test GDPR privacy consent
@@ -79,7 +79,7 @@ class _MyAppState extends State<MyApp> {
 
     // NOTE: Replace with your own app ID from https://www.onesignal.com
     await OneSignal.shared
-        .setAppId("380dc082-5231-4cc2-ab51-a03da5a0e4c2");
+        .setAppId("77e32082-ea27-42e3-a898-c72e141824ef");
 
     bool requiresConsent = await OneSignal.shared.requiresUserPrivacyConsent();
 
@@ -140,9 +140,9 @@ class _MyAppState extends State<MyApp> {
   void _handleGetDeviceState() async {
     print("Getting DeviceState");
     OneSignal.shared.getDeviceState().then((deviceState) {
-      print("DeviceState: ${deviceState.jsonRepresentation()}");
+      print("DeviceState: ${deviceState?.jsonRepresentation()}");
       this.setState(() {
-        _debugLabelString = deviceState.jsonRepresentation();
+        _debugLabelString = deviceState?.jsonRepresentation() ?? "Device state null";
       });
     });
   }
@@ -152,7 +152,7 @@ class _MyAppState extends State<MyApp> {
 
     print("Setting email");
 
-    OneSignal.shared.setEmail(email: _emailAddress).whenComplete(() {
+    OneSignal.shared.setEmail(email: _emailAddress!).whenComplete(() {
       print("Successfully set email");
     }).catchError((error) {
       print("Failed to set email with error: $error");
@@ -201,7 +201,9 @@ class _MyAppState extends State<MyApp> {
 
   void _handleSetExternalUserId() {
     print("Setting external user ID");
-    OneSignal.shared.setExternalUserId(_externalUserId).then((results) {
+    if (_externalUserId == null) return;
+
+    OneSignal.shared.setExternalUserId(_externalUserId!).then((results) {
         if (results == null) return;
 
         this.setState(() {
@@ -223,7 +225,10 @@ class _MyAppState extends State<MyApp> {
   void _handleSendNotification() async {
     var deviceState = await OneSignal.shared.getDeviceState();
 
-    var playerId = deviceState.userId;
+    if (deviceState == null || deviceState.userId == null)
+        return;
+
+    var playerId = deviceState.userId!;
 
     var imgUrlString =
         "http://cdn1-www.dogtime.com/assets/uploads/gallery/30-impossibly-cute-puppies/impossibly-cute-puppy-2.jpg";
@@ -249,7 +254,10 @@ class _MyAppState extends State<MyApp> {
   void _handleSendSilentNotification() async {
     var deviceState = await OneSignal.shared.getDeviceState();
 
-    var playerId = deviceState.userId;
+    if (deviceState == null || deviceState.userId == null)
+        return;
+
+    var playerId = deviceState.userId!;
 
     var notification = OSCreateNotification.silentNotification(
         playerIds: [playerId], additionalData: {'test': 'value'});
@@ -280,8 +288,8 @@ class _MyAppState extends State<MyApp> {
     OneSignal.shared.removeTriggerForKey("trigger_2");
 
     // Get the value for a trigger by its key
-    Object triggerValue = await OneSignal.shared.getTriggerValueForKey("trigger_3");
-    print("'trigger_3' key trigger value: " + triggerValue.toString());
+    Object? triggerValue = await OneSignal.shared.getTriggerValueForKey("trigger_3");
+    print("'trigger_3' key trigger value: ${triggerValue?.toString() ?? null}");
 
     // Create a list and bulk remove triggers based on keys supplied
     List<String> keys = ["trigger_1", "trigger_3"];

example/pubspec.yaml

@@ -57,3 +57,6 @@ flutter:
   #
   # For details regarding fonts from package dependencies,
   # see https://flutter.io/custom-fonts/#from-packages
+environment:
+  sdk: '>=2.12.0 <3.0.0'
+  flutter: ">=1.10.0 <2.0.0"

lib/onesignal_flutter.dart

@@ -40,12 +40,12 @@ class OneSignal {
   MethodChannel _outcomesChannel = const MethodChannel('OneSignal#outcomes');
 
   // event handlers
-  OpenedNotificationHandler _onOpenedNotification;
-  SubscriptionChangedHandler _onSubscriptionChangedHandler;
-  EmailSubscriptionChangeHandler _onEmailSubscriptionChangedHandler;
-  PermissionChangeHandler _onPermissionChangedHandler;
-  InAppMessageClickedHandler _onInAppMessageClickedHandler;
-  NotificationWillShowInForegroundHandler _onNotificationWillShowInForegroundHandler;
+  OpenedNotificationHandler? _onOpenedNotification;
+  SubscriptionChangedHandler? _onSubscriptionChangedHandler;
+  EmailSubscriptionChangeHandler? _onEmailSubscriptionChangedHandler;
+  PermissionChangeHandler? _onPermissionChangedHandler;
+  InAppMessageClickedHandler? _onInAppMessageClickedHandler;
+  NotificationWillShowInForegroundHandler? _onNotificationWillShowInForegroundHandler;
 
   // constructor method
   OneSignal() {
@@ -179,7 +179,7 @@ class OneSignal {
   /// waiting for this request to complete.
   Future<Map<String, dynamic>> sendTags(Map<String, dynamic> tags) async {
     Map<dynamic, dynamic> response =
-        await _tagsChannel.invokeMethod("OneSignal#sendTags", tags);
+        await (_tagsChannel.invokeMethod("OneSignal#sendTags", tags));
     return response.cast<String, dynamic>();
   }
 
@@ -190,7 +190,7 @@ class OneSignal {
   /// to finish.
   Future<Map<String, dynamic>> getTags() async {
     Map<dynamic, dynamic> tags =
-        await _tagsChannel.invokeMethod("OneSignal#getTags");
+        await (_tagsChannel.invokeMethod("OneSignal#getTags"));
     return tags.cast<String, dynamic>();
   }
 
@@ -207,15 +207,18 @@ class OneSignal {
   /// array of keys.
   Future<Map<String, dynamic>> deleteTags(List<String> keys) async {
     Map<dynamic, dynamic> response =
-        await _tagsChannel.invokeMethod("OneSignal#deleteTags", keys);
+        await (_tagsChannel.invokeMethod("OneSignal#deleteTags", keys));
     return response.cast<String, dynamic>();
   }
 
   /// Returns an `OSDeviceState` object, which contains the current device state
-  Future<OSDeviceState> getDeviceState() async {
+  Future<OSDeviceState?> getDeviceState() async {
     var json =
         await _channel.invokeMethod("OneSignal#getDeviceState");
 
+    if ((json.cast<String, dynamic>()).isEmpty)
+      return null;
+
     return OSDeviceState(json.cast<String, dynamic>());
   }
 
@@ -232,14 +235,14 @@ class OneSignal {
   Future<Map<String, dynamic>> postNotificationWithJson(
       Map<String, dynamic> json) async {
     Map<dynamic, dynamic> response =
-        await _channel.invokeMethod("OneSignal#postNotification", json);
+        await (_channel.invokeMethod("OneSignal#postNotification", json));
     return response.cast<String, dynamic>();
   }
 
   Future<Map<String, dynamic>> postNotification(
       OSCreateNotification notification) async {
-    Map<dynamic, dynamic> response = await _channel.invokeMethod(
-        "OneSignal#postNotification", notification.mapRepresentation());
+    Map<dynamic, dynamic> response = await (_channel.invokeMethod(
+        "OneSignal#postNotification", notification.mapRepresentation()));
     return response.cast<String, dynamic>();
   }
 
@@ -270,7 +273,7 @@ class OneSignal {
   /// Identity Verification. The email auth hash is a hash of your app's API key and the
   /// user ID. We recommend you generate this token from your backend server, do NOT
   /// store your API key in your app as this is highly insecure.
-  Future<void> setEmail({String email, String emailAuthHashToken}) async {
+  Future<void> setEmail({required String email, String? emailAuthHashToken}) async {
     return await _channel.invokeMethod("OneSignal#setEmail",
         {'email': email, 'emailAuthHashToken': emailAuthHashToken});
   }
@@ -284,16 +287,16 @@ class OneSignal {
   /// OneSignal allows you to set a custom ID for your users. This makes it so that
   /// if your app has its own user ID's, you can use your own custom user ID's with
   /// our API instead of having to save their OneSignal user ID's.
-  Future<Map<String, dynamic>> setExternalUserId(String externalId, [String authHashToken]) async {
+  Future<Map<String, dynamic>> setExternalUserId(String externalId, [String? authHashToken]) async {
     Map<dynamic, dynamic> results =
-        await _channel.invokeMethod("OneSignal#setExternalUserId", {'externalUserId' : externalId, 'authHashToken' : authHashToken});
+        await (_channel.invokeMethod("OneSignal#setExternalUserId", {'externalUserId' : externalId, 'authHashToken' : authHashToken}));
     return results.cast<String, dynamic>();
   }
 
   /// Removes the external user ID that was set for the current user.
   Future<Map<String, dynamic>> removeExternalUserId() async {
     Map<dynamic, dynamic> results =
-        await _channel.invokeMethod("OneSignal#removeExternalUserId");
+        await (_channel.invokeMethod("OneSignal#removeExternalUserId"));
     return results.cast<String, dynamic>();
   }
 
@@ -322,7 +325,7 @@ class OneSignal {
   }
 
   /// Get the trigger value associated with the key provided
-  Future<Object> getTriggerValueForKey(String key) async {
+  Future<Object?> getTriggerValueForKey(String key) async {
     return await _inAppMessagesChannel.invokeMethod("OneSignal#getTriggerValueForKey", key);
   }
 
@@ -368,27 +371,27 @@ class OneSignal {
   Future<Null> _handleMethod(MethodCall call) async {
     if (call.method == 'OneSignal#handleOpenedNotification' &&
         this._onOpenedNotification != null) {
-      this._onOpenedNotification(
+      this._onOpenedNotification!(
           OSNotificationOpenedResult(call.arguments.cast<String, dynamic>()));
     } else if (call.method == 'OneSignal#subscriptionChanged' &&
         this._onSubscriptionChangedHandler != null) {
-      this._onSubscriptionChangedHandler(
+      this._onSubscriptionChangedHandler!(
           OSSubscriptionStateChanges(call.arguments.cast<String, dynamic>()));
     } else if (call.method == 'OneSignal#permissionChanged' &&
         this._onPermissionChangedHandler != null) {
-      this._onPermissionChangedHandler(
+      this._onPermissionChangedHandler!(
            OSPermissionStateChanges(call.arguments.cast<String, dynamic>()));
     } else if (call.method == 'OneSignal#emailSubscriptionChanged' &&
         this._onEmailSubscriptionChangedHandler != null) {
-      this._onEmailSubscriptionChangedHandler(
+      this._onEmailSubscriptionChangedHandler!(
           OSEmailSubscriptionStateChanges(call.arguments.cast<String, dynamic>()));
     } else if (call.method == 'OneSignal#handleClickedInAppMessage' &&
         this._onInAppMessageClickedHandler != null) {
-      this._onInAppMessageClickedHandler(
+      this._onInAppMessageClickedHandler!(
           OSInAppMessageAction(call.arguments.cast<String, dynamic>()));
     } else if (call.method == 'OneSignal#handleNotificationWillShowInForeground' &&
         this._onNotificationWillShowInForegroundHandler != null) {
-      this._onNotificationWillShowInForegroundHandler(
+      this._onNotificationWillShowInForegroundHandler!(
           OSNotificationReceivedEvent(call.arguments.cast<String, dynamic>()));
     }
     return null;

lib/src/create_notification.dart

@@ -11,90 +11,90 @@ class OSCreateNotification extends JSONStringRepresentable {
   List<String> playerIds;
 
   /// The notification's content (excluding title)
-  String content;
+  String? content;
 
   /// The language code (ie. "en" for English) for this notification
   /// defaults to "en" (English)
-  String languageCode;
+  String? languageCode;
 
   /// The title/heading for the notification
-  String heading;
+  String? heading;
 
   /// The subtitle for the notification (iOS 10+ only)
-  String subtitle;
+  String? subtitle;
 
   /// Tells the app to launch in the background (iOS only)
-  bool contentAvailable;
+  bool? contentAvailable;
 
   /// Tells the app to launch the Notification Service extension,
   /// which can mutate your notification (ie. download attachments)
-  bool mutableContent;
+  bool? mutableContent;
 
   /// Additional data you wish to send with the notification
-  Map<String, dynamic> additionalData;
+  Map<String, dynamic>? additionalData;
 
   /// The URL to open when the user taps the notification
-  String url;
+  String? url;
 
   /// Media (images, videos, etc.) for iOS
   /// Maps a custom ID to a resource URL
   /// in the format {'id' : 'https://.....'}
-  Map<String, String> iosAttachments;
+  Map<String, String>? iosAttachments;
 
   /// An image to use as the big picture (android only)
-  String bigPicture;
+  String? bigPicture;
 
   /// A list of buttons to attach to the notification
-  List<OSActionButton> buttons;
+  List<OSActionButton>? buttons;
 
   /// The category identifier for iOS (controls various aspects
   /// of the notification, for example, whether to launch a
   /// Notification Content Extension) (iOS only)
-  String iosCategory;
+  String? iosCategory;
 
   /// The sound to play (iOS only)
-  String iosSound;
+  String? iosSound;
 
   /// The sound to play (Android only)
-  String androidSound;
+  String? androidSound;
 
   /// A small icon (Android only)
   /// Can be a drawable resource name or a URL
-  String androidSmallIcon;
+  String? androidSmallIcon;
 
   /// A large icon (android only)
   /// Can be a drawable resource name or a URL
-  String androidLargeIcon;
+  String? androidLargeIcon;
 
   /// The Android Oreo Notification Category to send the notification under
-  String androidChannelId;
+  String? androidChannelId;
 
   /// can be 'Increase' or 'SetTo'
-  OSCreateNotificationBadgeType iosBadgeType;
+  OSCreateNotificationBadgeType? iosBadgeType;
 
   /// The actual badge count to either set to directly, or increment by
   /// To decrement the user's badge count, send a negative value
-  int iosBadgeCount;
+  int? iosBadgeCount;
 
   /// If multiple notifications have the same collapse ID, only the most
   /// recent notification will be shown
-  String collapseId;
+  String? collapseId;
 
   /// Allows you to send a notification at a specific date
-  DateTime sendAfter;
+  DateTime? sendAfter;
 
   /// You can use several options to send notifications at specific times
   /// ie. you can send notifications to different user's at the same time
   /// in each timezone with the 'timezone' delayedOption
-  OSCreateNotificationDelayOption delayedOption;
+  OSCreateNotificationDelayOption? delayedOption;
 
   /// Used with delayedOption == timezone, lets you specify what time of day
   /// each user should receive the notification, ie. "9:00 AM"
-  String deliveryTimeOfDay;
+  String? deliveryTimeOfDay;
 
   OSCreateNotification(
-      {@required this.playerIds,
-      @required this.content,
+      {required this.playerIds,
+      required this.content,
       this.languageCode,
       this.heading,
       this.subtitle,
@@ -119,7 +119,7 @@ class OSCreateNotification extends JSONStringRepresentable {
       this.deliveryTimeOfDay});
 
   OSCreateNotification.silentNotification(
-      {@required this.playerIds,
+      {required this.playerIds,
       this.additionalData,
       this.sendAfter,
       this.delayedOption,
@@ -164,16 +164,16 @@ class OSCreateNotification extends JSONStringRepresentable {
 
     // adds optional parameters that require transformations
     if (this.sendAfter != null)
-      json['send_after'] = dateToStringWithOffset(this.sendAfter);
+      json['send_after'] = dateToStringWithOffset(this.sendAfter!);
     if (this.iosBadgeType != null)
       json['ios_badgeType'] = convertEnumCaseToValue(this.iosBadgeType);
     if (this.delayedOption != null)
       json['delayed_option'] = convertEnumCaseToValue(this.delayedOption);
 
     // adds buttons
     if (this.buttons != null) {
-      var btns = List<Map<String, dynamic>>();
-      this.buttons.forEach((btn) => btns.add(btn.mapRepresentation()));
+      var btns = [];
+      this.buttons!.forEach((btn) => btns.add(btn.mapRepresentation()));
       json['buttons'] = btns;
     }