Migration to null safety (#11)

* Migration to null safety

* PR comment fixed

* Spacing revert

* CI flutter version update

.github/workflows/ci.yaml

@@ -14,7 +14,7 @@ jobs:
 
       - uses: subosito/flutter-action@v1.4.0
         with:
-          flutter-version: 1.22.4
+          flutter-version: 2.0.5
           channel: "stable"
 
       - name: Install Dependencies

example/lib/main.dart

@@ -48,7 +48,7 @@ class _MyAppState extends State<MyApp> {
     var platform =
         Theme.of(context).platform.toString().split('.')[1].toLowerCase();
     try {
-      bool featureEnabled = await optimizelyPlugin.isFeatureEnabled(
+      bool? featureEnabled = await optimizelyPlugin.isFeatureEnabled(
         'price_filter',
         'user@example.org',
         {'platform': platform},
@@ -79,7 +79,7 @@ class _MyAppState extends State<MyApp> {
         'user@example.org',
         {'platform': platform},
       );
-      int minPrice = variables['min_price'];
+      int? minPrice = variables['min_price'];
       minPriceVariable = "min_price variable is: ${minPrice.toString()}.";
     } catch (e) {
       minPriceVariable = "Failed to get min_price variable from feature: '$e'.";
@@ -106,7 +106,7 @@ class _MyAppState extends State<MyApp> {
               Center(
                 child: Text(_priceFilterFlag),
               ),
-              RaisedButton(
+              ElevatedButton(
                 child: Text('Get Price Filter Flag'),
                 onPressed: () {
                   getPriceFilterFlag();
@@ -116,7 +116,7 @@ class _MyAppState extends State<MyApp> {
               Center(
                 child: Text(_minPriceVariable),
               ),
-              RaisedButton(
+              ElevatedButton(
                 child: Text('Get Price Filter Min Price'),
                 onPressed: () {
                   getPriceFilterMinPrice();

example/pubspec.yaml

@@ -6,7 +6,7 @@ description: Demonstrates how to use the optimizely_plugin plugin.
 publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: ">=2.12.0 <3.0.0"
 
 dependencies:
   flutter:
@@ -22,7 +22,7 @@ dependencies:
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
-  cupertino_icons: ^0.1.3
+  cupertino_icons: ^1.0.2
 
 dev_dependencies:
   flutter_test:

example/test/widget_test.dart

@@ -7,7 +7,6 @@
 
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
-
 import 'package:optimizely_plugin_example/main.dart';
 
 void main() {
@@ -18,8 +17,8 @@ void main() {
     // Verify that platform version is retrieved.
     expect(
       find.byWidgetPredicate(
-        (Widget widget) => widget is Text &&
-                           widget.data.startsWith('Running on:'),
+        (Widget widget) =>
+            widget is Text && widget.data!.startsWith('Running on:'),
       ),
       findsOneWidget,
     );

lib/optimizely_plugin.dart

@@ -26,7 +26,7 @@ class OptimizelyPlugin {
     });
   }
 
-  Future<bool> isFeatureEnabled(
+  Future<bool?> isFeatureEnabled(
     String featureKey,
     userID,
     Map<String, dynamic> attributes,

pubspec.yaml

@@ -1,11 +1,11 @@
 name: optimizely_plugin
 description: Flutter plugin for Optimizely SDK
-version: 0.1.2
+version: 0.1.3
 homepage: https://www.policygenius.com/
 repository: https://github.com/policygenius/optimizely-plugin
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: ">=2.12.0 <3.0.0"
   flutter: ">=1.20.0 <2.0.0"
 
 dependencies: