applied dart fix and updated flutter versions

.github/workflows/flutter-codestyle.yml

@@ -20,10 +20,10 @@ jobs:
     steps:
     - uses: actions/checkout@v3
 
-    - name: Install Flutter 2.8.1
+    - name: Install Flutter 3.22.2
       uses: subosito/flutter-action@v2
       with:
-        flutter-version: 2.8.1
+        flutter-version: 3.22.2
 
     - name: Run Binding Analyzer
       run: flutter analyze --no-fatal-infos --no-fatal-warnings

.github/workflows/flutter-demos.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        flutter-version: ['2.8.1', '3.0.4']
+        flutter-version: ['3.3.0', '3.22.2']
 
     steps:
     - uses: actions/checkout@v3
@@ -52,10 +52,10 @@ jobs:
 
   build-ios:
     name: Build iOS demo
-    runs-on: macos-11
+    runs-on: macos-12
     strategy:
       matrix:
-        flutter-version: ['2.8.1', '3.0.4']
+        flutter-version: ['3.3.0', '3.22.2']
 
     steps:
     - uses: actions/checkout@v3

demo/flutter/lib/main.dart

@@ -214,7 +214,7 @@ class _MyAppState extends State<MyApp> {
 
   buildStartButton(BuildContext context) {
     final ButtonStyle buttonStyle = ElevatedButton.styleFrom(
-        primary: picoBlue,
+        backgroundColor: picoBlue,
         shape: BeveledRectangleBorder(),
         textStyle: TextStyle(color: Colors.white));
 

demo/flutter/pubspec.yaml

@@ -6,8 +6,8 @@ publish_to: 'none'
 version: 1.0.0
 
 environment:
-  sdk: ">=2.15.0 <4.0.0"
-  flutter: ">=2.8.1"
+  sdk: ">=2.18.0 <4.0.0"
+  flutter: ">=3.3.0"
 
 dependencies:
   flutter: