fix some stuff

- remove unnecessary containers
- bump linting version in pubspec.yml
- make `isLargeScreen` and `isSmallScreen` a geter
- add decimal points to double values
- remove unused SizedBox
- use const constructor where possible
- remove residual code
- fix help_screen AppBar
- Fix historyNavToolbar padding

fix styling of drawer
- fix the padding of the drawer elements.


cleanup settings
- removes unused properties
- fixes ListItemDivider height

src/ui/flutter_app/lib/main.dart

@@ -96,7 +96,7 @@ Future<void> main() async {
     [DeviceOrientation.portraitUp, DeviceOrientation.portraitDown],
   );
 
-  if (Platform.isAndroid && isLargeScreen()) {
+  if (Platform.isAndroid && isLargeScreen) {
     SystemChrome.setSystemUIOverlayStyle(
       const SystemUiOverlayStyle(
         statusBarColor: Colors.transparent,
@@ -108,7 +108,7 @@ Future<void> main() async {
     );
   }
 
-  if (isSmallScreen()) {
+  if (isSmallScreen) {
     SystemChrome.setEnabledSystemUIMode(SystemUiMode.manual, overlays: []);
   }
 }

src/ui/flutter_app/lib/screens/about_page.dart

@@ -34,7 +34,6 @@ import 'list_item_divider.dart';
 import 'oss_license_page.dart';
 
 class AboutPage extends StatelessWidget {
-  // String _version = "";
   final String tag = "[about] ";
 
   String get mode {

src/ui/flutter_app/lib/screens/game_page.dart

@@ -49,12 +49,9 @@ import 'game_settings_page.dart';
 double boardWidth = 0.0;
 
 class GamePage extends StatefulWidget {
-  static double boardMargin = AppTheme.boardMargin;
-  static double screenPaddingH = AppTheme.boardScreenPaddingH;
-
   final EngineType engineType;
 
-  const GamePage(this.engineType);
+  const GamePage(this.engineType, {Key? key}) : super(key: key);
 
   @override
   _GamePageState createState() => _GamePageState();
@@ -64,6 +61,9 @@ class _GamePageState extends State<GamePage>
     with RouteAware, SingleTickerProviderStateMixin {
   final Engine _engine = NativeEngine();
 
+  double screenPaddingH = AppTheme.boardScreenPaddingH;
+  final double boardMargin = AppTheme.boardMargin;
+
   String? _tip = '';
   bool isReady = false;
   bool isGoingToHistory = false;
@@ -77,26 +77,9 @@ class _GamePageState extends State<GamePage>
   late AnimationController _animationController;
   late Animation<double> animation;
   bool disposed = false;
-  bool ltr = true;
+  late final bool ltr;
   final String tag = "[game_page]";
 
-  @override
-  void initState() {
-    debugPrint("$tag Engine type: ${widget.engineType}");
-
-    gameInstance.setWhoIsAi(widget.engineType);
-
-    super.initState();
-    gameInstance.init();
-    _engine.startup();
-
-    timer = Timer.periodic(const Duration(microseconds: 100), (Timer t) {
-      _setReadyState();
-    });
-
-    _initAnimation();
-  }
-
   Future<void> _setReadyState() async {
     debugPrint("$tag Check if need to set Ready state...");
     if (!isReady && mounted && Config.settingsLoaded) {
@@ -124,9 +107,7 @@ class _GamePageState extends State<GamePage>
       begin: 1.27, // sqrt(1.618) = 1.272
       end: 1.0,
     ).animate(_animationController)
-      ..addListener(() {
-        setState(() {});
-      });
+      ..addListener(() => setState(() {}));
 
     _animationController.addStatusListener((state) {
       if (state == AnimationStatus.completed ||
@@ -904,6 +885,44 @@ class _GamePageState extends State<GamePage>
   }
 
   void onMoveButtonPressed() {
+    final List<Widget> _historyNavigation = [
+      SimpleDialogOption(
+        onPressed: onTakeBackButtonPressed,
+        child: Text(
+          S.of(context).takeBack,
+          style: AppTheme.simpleDialogOptionTextStyle,
+          textAlign: TextAlign.center,
+        ),
+      ),
+      const SizedBox(height: AppTheme.sizedBoxHeight),
+      SimpleDialogOption(
+        onPressed: onStepForwardButtonPressed,
+        child: Text(
+          S.of(context).stepForward,
+          style: AppTheme.simpleDialogOptionTextStyle,
+          textAlign: TextAlign.center,
+        ),
+      ),
+      const SizedBox(height: AppTheme.sizedBoxHeight),
+      SimpleDialogOption(
+        onPressed: onTakeBackAllButtonPressed,
+        child: Text(
+          S.of(context).takeBackAll,
+          style: AppTheme.simpleDialogOptionTextStyle,
+          textAlign: TextAlign.center,
+        ),
+      ),
+      const SizedBox(height: AppTheme.sizedBoxHeight),
+      SimpleDialogOption(
+        onPressed: onStepForwardAllButtonPressed,
+        child: Text(
+          S.of(context).stepForwardAll,
+          style: AppTheme.simpleDialogOptionTextStyle,
+          textAlign: TextAlign.center,
+        ),
+      ),
+      const SizedBox(height: AppTheme.sizedBoxHeight),
+    ];
     showModalBottomSheet(
       context: context,
       backgroundColor: Colors.transparent,
@@ -912,50 +931,7 @@ class _GamePageState extends State<GamePage>
         child: SimpleDialog(
           backgroundColor: Colors.transparent,
           children: <Widget>[
-            if (!Config.isHistoryNavigationToolbarShown)
-              SimpleDialogOption(
-                onPressed: onTakeBackButtonPressed,
-                child: Text(
-                  S.of(context).takeBack,
-                  style: AppTheme.simpleDialogOptionTextStyle,
-                  textAlign: TextAlign.center,
-                ),
-              ),
-            if (!Config.isHistoryNavigationToolbarShown)
-              const SizedBox(height: AppTheme.sizedBoxHeight),
-            if (!Config.isHistoryNavigationToolbarShown)
-              SimpleDialogOption(
-                onPressed: onStepForwardButtonPressed,
-                child: Text(
-                  S.of(context).stepForward,
-                  style: AppTheme.simpleDialogOptionTextStyle,
-                  textAlign: TextAlign.center,
-                ),
-              ),
-            if (!Config.isHistoryNavigationToolbarShown)
-              const SizedBox(height: AppTheme.sizedBoxHeight),
-            if (!Config.isHistoryNavigationToolbarShown)
-              SimpleDialogOption(
-                onPressed: onTakeBackAllButtonPressed,
-                child: Text(
-                  S.of(context).takeBackAll,
-                  style: AppTheme.simpleDialogOptionTextStyle,
-                  textAlign: TextAlign.center,
-                ),
-              ),
-            if (!Config.isHistoryNavigationToolbarShown)
-              const SizedBox(height: AppTheme.sizedBoxHeight),
-            if (!Config.isHistoryNavigationToolbarShown)
-              SimpleDialogOption(
-                onPressed: onStepForwardAllButtonPressed,
-                child: Text(
-                  S.of(context).stepForwardAll,
-                  style: AppTheme.simpleDialogOptionTextStyle,
-                  textAlign: TextAlign.center,
-                ),
-              ),
-            if (!Config.isHistoryNavigationToolbarShown)
-              const SizedBox(height: AppTheme.sizedBoxHeight),
+            if (!Config.isHistoryNavigationToolbarShown) ..._historyNavigation,
             SimpleDialogOption(
               onPressed: onMoveListButtonPressed,
               child: Text(
@@ -1430,21 +1406,23 @@ class _GamePageState extends State<GamePage>
     }
   }
 
-  void calcScreenPaddingH() {
+  double get _screenPaddingH {
     //
     // when screen's height/width rate is less than 16/9, limit width of board
     final windowSize = MediaQuery.of(context).size;
     final double height = windowSize.height;
     double width = windowSize.width;
 
+    // TODO: maybe use windowSize.aspectratio
     if (height / width < 16.0 / 9.0) {
       width = height * 9 / 16;
-      GamePage.screenPaddingH =
-          (windowSize.width - width) / 2 - AppTheme.boardMargin;
+      return (windowSize.width - width) / 2 - AppTheme.boardMargin;
+    } else {
+      return AppTheme.boardScreenPaddingH;
     }
   }
 
-  Widget createPageHeader() {
+  Widget get header {
     final Map<EngineType, IconData> engineTypeToIconLeft = {
       EngineType.humanVsAi: Config.aiMovesFirst
           ? FluentIcons.bot_24_filled
@@ -1467,17 +1445,14 @@ class _GamePageState extends State<GamePage>
       EngineType.testViaLAN: FluentIcons.wifi_1_24_filled,
     };
 
-    final IconData iconArrow = getIconArrow();
-
     final iconColor = Color(Config.messageColor);
 
     final iconRow = Row(
+      mainAxisAlignment: MainAxisAlignment.center,
       children: <Widget>[
-        const Expanded(child: SizedBox()),
         Icon(engineTypeToIconLeft[widget.engineType], color: iconColor),
         Icon(iconArrow, color: iconColor),
         Icon(engineTypeToIconRight[widget.engineType], color: iconColor),
-        const Expanded(child: SizedBox()),
       ],
     );
 
@@ -1511,7 +1486,7 @@ class _GamePageState extends State<GamePage>
     );
   }
 
-  IconData getIconArrow() {
+  IconData get iconArrow {
     IconData iconArrow = FluentIcons.code_24_regular;
 
     if (gameInstance.position.phase == Phase.gameOver) {
@@ -1547,15 +1522,11 @@ class _GamePageState extends State<GamePage>
     return iconArrow;
   }
 
-  Widget createBoard() {
-    boardWidth =
-        MediaQuery.of(context).size.width - GamePage.screenPaddingH * 2;
+  Widget get board {
+    boardWidth = MediaQuery.of(context).size.width - screenPaddingH * 2;
 
     return Container(
-      margin: EdgeInsets.symmetric(
-        horizontal: GamePage.screenPaddingH,
-        vertical: GamePage.boardMargin,
-      ),
+      margin: EdgeInsets.symmetric(vertical: boardMargin),
       child: Board(
         width: boardWidth,
         onBoardTap: onBoardTap,
@@ -1630,7 +1601,7 @@ class _GamePageState extends State<GamePage>
     return ret;
   }
 
-  Widget createToolbar() {
+  Widget get toolbar {
     final gameButton = TextButton(
       onPressed: onGameButtonPressed,
       child: Column(
@@ -1704,94 +1675,70 @@ class _GamePageState extends State<GamePage>
         borderRadius: BorderRadius.circular(5),
         color: Color(Config.mainToolbarBackgroundColor),
       ),
-      margin: EdgeInsets.symmetric(horizontal: GamePage.screenPaddingH),
+      margin: EdgeInsets.symmetric(horizontal: screenPaddingH),
       padding: const EdgeInsets.symmetric(vertical: 2),
       child: Row(
+        mainAxisAlignment: MainAxisAlignment.spaceAround,
         textDirection: TextDirection.ltr,
         children: <Widget>[
-          const Expanded(child: SizedBox()),
           gameButton,
-          const Expanded(child: SizedBox()),
           optionsButton,
-          const Expanded(child: SizedBox()),
           moveButton,
-          const Expanded(child: SizedBox()), //dashboard_outlined
           infoButton,
-          const Expanded(child: SizedBox()),
         ],
       ),
     );
   }
 
-  Widget createHistoryNavigationToolbar() {
+  Widget get historyNavToolbar {
     final takeBackAllButton = TextButton(
-      child: Column(
-        // Replace with a Row for horizontal icon + text
-        children: <Widget>[
-          Semantics(
-            label: S.of(context).takeBackAll,
-            child: Icon(
-              ltr
-                  ? FluentIcons.arrow_previous_24_regular
-                  : FluentIcons.arrow_next_24_regular,
-              color: Color(Config.navigationToolbarIconColor),
-            ),
-          ),
-        ],
+      child: Semantics(
+        label: S.of(context).takeBackAll,
+        child: Icon(
+          ltr
+              ? FluentIcons.arrow_previous_24_regular
+              : FluentIcons.arrow_next_24_regular,
+          color: Color(Config.navigationToolbarIconColor),
+        ),
       ),
       onPressed: () => onTakeBackAllButtonPressed(pop: false),
     );
 
     final takeBackButton = TextButton(
-      child: Column(
-        // Replace with a Row for horizontal icon + text
-        children: <Widget>[
-          Semantics(
-            label: S.of(context).takeBack,
-            child: Icon(
-              ltr
-                  ? FluentIcons.chevron_left_24_regular
-                  : FluentIcons.chevron_right_24_regular,
-              color: Color(Config.navigationToolbarIconColor),
-            ),
-          ),
-        ],
+      child: Semantics(
+        label: S.of(context).takeBack,
+        child: Icon(
+          ltr
+              ? FluentIcons.chevron_left_24_regular
+              : FluentIcons.chevron_right_24_regular,
+          color: Color(Config.navigationToolbarIconColor),
+        ),
       ),
       onPressed: () => onTakeBackButtonPressed(pop: false),
     );
 
     final stepForwardButton = TextButton(
-      child: Column(
-        // Replace with a Row for horizontal icon + text
-        children: <Widget>[
-          Semantics(
-            label: S.of(context).stepForward,
-            child: Icon(
-              ltr
-                  ? FluentIcons.chevron_right_24_regular
-                  : FluentIcons.chevron_left_24_regular,
-              color: Color(Config.navigationToolbarIconColor),
-            ),
-          ),
-        ],
+      child: Semantics(
+        label: S.of(context).stepForward,
+        child: Icon(
+          ltr
+              ? FluentIcons.chevron_right_24_regular
+              : FluentIcons.chevron_left_24_regular,
+          color: Color(Config.navigationToolbarIconColor),
+        ),
       ),
       onPressed: () => onStepForwardButtonPressed(pop: false),
     );
 
     final stepForwardAllButton = TextButton(
-      child: Column(
-        // Replace with a Row for horizontal icon + text
-        children: <Widget>[
-          Semantics(
-            label: S.of(context).stepForwardAll,
-            child: Icon(
-              ltr
-                  ? FluentIcons.arrow_next_24_regular
-                  : FluentIcons.arrow_previous_24_regular,
-              color: Color(Config.navigationToolbarIconColor),
-            ),
-          ),
-        ],
+      child: Semantics(
+        label: S.of(context).stepForwardAll,
+        child: Icon(
+          ltr
+              ? FluentIcons.arrow_next_24_regular
+              : FluentIcons.arrow_previous_24_regular,
+          color: Color(Config.navigationToolbarIconColor),
+        ),
       ),
       onPressed: () => onStepForwardAllButtonPressed(pop: false),
     );
@@ -1801,25 +1748,41 @@ class _GamePageState extends State<GamePage>
         borderRadius: BorderRadius.circular(5),
         color: Color(Config.navigationToolbarBackgroundColor),
       ),
-      margin: EdgeInsets.symmetric(horizontal: GamePage.screenPaddingH),
+      margin: EdgeInsets.symmetric(
+        horizontal: screenPaddingH,
+        vertical: 1,
+      ),
       padding: const EdgeInsets.symmetric(vertical: 2),
       child: Row(
+        mainAxisAlignment: MainAxisAlignment.spaceAround,
         textDirection: TextDirection.ltr,
         children: <Widget>[
-          const Expanded(child: SizedBox()),
           takeBackAllButton,
-          const Expanded(child: SizedBox()),
           takeBackButton,
-          const Expanded(child: SizedBox()),
           stepForwardButton,
-          const Expanded(child: SizedBox()), //dashboard_outlined
           stepForwardAllButton,
-          const Expanded(child: SizedBox()),
         ],
       ),
     );
   }
 
+  @override
+  void initState() {
+    debugPrint("$tag Engine type: ${widget.engineType}");
+
+    gameInstance.setWhoIsAi(widget.engineType);
+
+    super.initState();
+    gameInstance.init();
+    _engine.startup();
+
+    timer = Timer.periodic(const Duration(microseconds: 100), (Timer t) {
+      _setReadyState();
+    });
+
+    _initAnimation();
+  }
+
   @override
   void didChangeDependencies() {
     super.didChangeDependencies();
@@ -1827,23 +1790,16 @@ class _GamePageState extends State<GamePage>
       this,
       ModalRoute.of(context)! as PageRoute<dynamic>,
     );
+    screenPaddingH = _screenPaddingH;
+    ltr = getBidirectionality(context) == Bidirectionality.leftToRight;
   }
 
   @override
   Widget build(BuildContext context) {
-    ltr = getBidirectionality(context) == Bidirectionality.leftToRight;
-
     if (_tip == '') {
       _tip = S.of(context).welcome;
     }
 
-    calcScreenPaddingH();
-
-    final header = createPageHeader();
-    final board = createBoard();
-    final toolbar = createToolbar();
-    final historyNavToolbar = createHistoryNavigationToolbar();
-
     return Scaffold(
       backgroundColor: Color(Config.darkBackgroundColor),
       body: Column(

src/ui/flutter_app/lib/screens/game_settings_page.dart

@@ -194,10 +194,8 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
     return <Widget>[
       Text(S.of(context).whoMovesFirst, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsSwitchListTile(
-            context: context,
             value: !Config.aiMovesFirst,
             onChanged: setWhoMovesFirst,
             titleString:
@@ -208,7 +206,6 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).difficulty, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).skillLevel,
@@ -224,7 +221,6 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).aisPlayStyle, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).algorithm,
@@ -232,66 +228,50 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
             onTap: setAlgorithm,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.drawOnHumanExperience,
             onChanged: setDrawOnHumanExperience,
             titleString: S.of(context).drawOnHumanExperience,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.considerMobility,
             onChanged: setConsiderMobility,
             titleString: S.of(context).considerMobility,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.aiIsLazy,
             onChanged: setAiIsLazy,
             titleString: S.of(context).passive,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.shufflingEnabled,
             onChanged: setShufflingEnabled,
             titleString: S.of(context).shufflingEnabled,
           ),
         ],
       ),
+      if (!Platform.isWindows) const SizedBox(height: AppTheme.sizedBoxHeight),
       if (!Platform.isWindows)
-        const SizedBox(height: AppTheme.sizedBoxHeight)
-      else
-        const SizedBox(height: 0.0, width: 0.0),
-      if (!Platform.isWindows)
-        Text(S.of(context).playSounds, style: AppTheme.settingsHeaderStyle)
-      else
-        const SizedBox(height: 0.0, width: 0.0),
+        Text(S.of(context).playSounds, style: AppTheme.settingsHeaderStyle),
       if (!Platform.isWindows)
         SettingsCard(
-          context: context,
           children: <Widget>[
             SettingsSwitchListTile(
-              context: context,
               value: Config.toneEnabled,
               onChanged: setTone,
               titleString: S.of(context).playSoundsInTheGame,
             ),
             SettingsSwitchListTile(
-              context: context,
               value: Config.keepMuteWhenTakingBack,
               onChanged: setKeepMuteWhenTakingBack,
               titleString: S.of(context).keepMuteWhenTakingBack,
             ),
           ],
-        )
-      else
-        const SizedBox(height: 0.0, width: 0.0),
+        ),
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).accessibility, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsSwitchListTile(
-            context: context,
             value: Config.screenReaderSupport,
             onChanged: setScreenReaderSupport,
             titleString: S.of(context).screenReaderSupport,
@@ -301,7 +281,6 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).restore, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).restoreDefaultSettings,
@@ -317,22 +296,18 @@ class _GameSettingsPageState extends State<GameSettingsPage> {
         ),
       if (Developer.developerModeEnabled)
         SettingsCard(
-          context: context,
           children: <Widget>[
             SettingsSwitchListTile(
-              context: context,
               value: Config.developerMode,
               onChanged: setDeveloperMode,
               titleString: S.of(context).developerMode,
             ),
             SettingsSwitchListTile(
-              context: context,
               value: Config.experimentsEnabled,
               onChanged: setExperimentsEnabled,
               titleString: S.of(context).experiments,
             ),
             SettingsSwitchListTile(
-              context: context,
               value: Config.isAutoRestart,
               onChanged: setIsAutoRestart,
               titleString: S.of(context).isAutoRestart,

src/ui/flutter_app/lib/screens/help_screen.dart

@@ -8,12 +8,12 @@ class HelpScreen extends StatelessWidget {
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
+        elevation: 0.0,
+        backgroundColor: Color(Config.darkBackgroundColor),
         centerTitle: true,
         title: Text(
           S.of(context).howToPlay,
           style: TextStyle(
-            fontSize: Config.fontSize + 4,
-            fontWeight: FontWeight.bold,
             color: AppTheme.helpTextColor,
           ),
         ),

src/ui/flutter_app/lib/screens/home_drawer.dart

@@ -186,7 +186,7 @@ class HomeDrawer extends StatelessWidget {
         children: <Widget>[
           animatedBuilder,
           Padding(
-            padding: EdgeInsets.only(top: isLargeScreen() ? 30 : 8, left: 4),
+            padding: EdgeInsets.only(top: isLargeScreen ? 30 : 8, left: 4),
             child: ExcludeSemantics(child: animatedTextKit),
           ),
         ],
@@ -269,7 +269,7 @@ class HomeDrawer extends StatelessWidget {
             0.0,
           ),
           child: Padding(
-            padding: const EdgeInsets.symmetric(vertical: 8),
+            padding: const EdgeInsets.symmetric(horizontal: 8),
             child: Container(
               width: MediaQuery.of(context).size.width * 0.75 - 64,
               height: 46,
@@ -298,7 +298,7 @@ class HomeDrawer extends StatelessWidget {
     final stack = Stack(
       children: <Widget>[
         Padding(
-          padding: const EdgeInsets.symmetric(vertical: 8.0),
+          padding: const EdgeInsets.symmetric(horizontal: 8.0),
           child: Row(
             children: <Widget>[
               const SizedBox(height: 46.0, width: 6.0),
@@ -326,7 +326,7 @@ class HomeDrawer extends StatelessWidget {
             ],
           ),
         ),
-        if (screenIndex == listItem.index) animatedBuilder else const SizedBox()
+        if (screenIndex == listItem.index) animatedBuilder,
       ],
     );
 
@@ -336,9 +336,7 @@ class HomeDrawer extends StatelessWidget {
       child: InkWell(
         splashColor: AppTheme.drawerSplashColor,
         highlightColor: AppTheme.drawerHighlightColor,
-        onTap: () {
-          navigationToScreen(listItem.index);
-        },
+        onTap: () => navigationToScreen(listItem.index),
         child: stack,
       ),
     );

src/ui/flutter_app/lib/screens/list_item_divider.dart

@@ -29,6 +29,7 @@ class ListItemDivider extends StatelessWidget {
     return Divider(
       indent: 16,
       endIndent: 16,
+      height: 1.0,
       thickness: 1.0,
       color: AppTheme.listItemDividerColor,
     );

src/ui/flutter_app/lib/screens/personalization_settings_page.dart

@@ -387,7 +387,6 @@ class _PersonalizationSettingsPageState
     return <Widget>[
       Text(S.of(context).display, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).language,
@@ -398,19 +397,16 @@ class _PersonalizationSettingsPageState
             onTap: () => setLanguage(context, langCallback),
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.isPieceCountInHandShown,
             onChanged: setIsPieceCountInHandShown,
             titleString: S.of(context).isPieceCountInHandShown,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.isNotationsShown,
             onChanged: setIsNotationsShown,
             titleString: S.of(context).isNotationsShown,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.isHistoryNavigationToolbarShown,
             onChanged: setIsHistoryNavigationToolbarShown,
             titleString: S.of(context).isHistoryNavigationToolbarShown,
@@ -440,7 +436,6 @@ class _PersonalizationSettingsPageState
             onTap: setAnimationDuration,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.standardNotationEnabled,
             onChanged: setStandardNotationEnabled,
             titleString: S.of(context).standardNotation,
@@ -450,7 +445,6 @@ class _PersonalizationSettingsPageState
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).color, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).boardColor,

src/ui/flutter_app/lib/screens/rule_settings_page.dart

@@ -54,7 +54,6 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
     return <Widget>[
       Text(S.of(context).general, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsListTile(
             titleString: S.of(context).piecesCount,
@@ -63,7 +62,6 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
             onTap: setNTotalPiecesEachSide,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.hasDiagonalLines,
             onChanged: setHasDiagonalLines,
             titleString: S.of(context).hasDiagonalLines,
@@ -82,7 +80,6 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
             onTap: setEndgameNMoveRule,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.threefoldRepetitionRule,
             onChanged: setThreefoldRepetitionRule,
             titleString: S.of(context).threefoldRepetitionRule,
@@ -93,17 +90,14 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).placing, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsSwitchListTile(
-            context: context,
             value: Config.hasBannedLocations,
             onChanged: setHasBannedLocations,
             titleString: S.of(context).hasBannedLocations,
             subtitleString: S.of(context).hasBannedLocations_Detail,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.isWhiteLoseButNotDrawWhenBoardFull,
             onChanged: setIsWhiteLoseButNotDrawWhenBoardFull,
             titleString: S.of(context).isWhiteLoseButNotDrawWhenBoardFull,
@@ -111,7 +105,6 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
                 S.of(context).isWhiteLoseButNotDrawWhenBoardFull_Detail,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.mayOnlyRemoveUnplacedPieceInPlacingPhase,
             onChanged: setMayOnlyRemoveUnplacedPieceInPlacingPhase,
             titleString: S.of(context).removeUnplacedPiece,
@@ -122,11 +115,9 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).moving, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           if (Config.experimentsEnabled)
             SettingsSwitchListTile(
-              context: context,
               value: Config.mayMoveInPlacingPhase,
               onChanged: setMayMoveInPlacingPhase,
               titleString: S.of(context).mayMoveInPlacingPhase,
@@ -134,14 +125,12 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
             )
           else
             SettingsSwitchListTile(
-              context: context,
               value: Config.isDefenderMoveFirst,
               onChanged: setIsDefenderMoveFirst,
               titleString: S.of(context).isDefenderMoveFirst,
               subtitleString: S.of(context).isDefenderMoveFirst_Detail,
             ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.isLoseButNotChangeSideWhenNoWay,
             onChanged: setIsLoseButNotChangeSideWhenNoWay,
             titleString: S.of(context).isLoseButNotChangeSideWhenNoWay,
@@ -153,10 +142,8 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).mayFly, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsSwitchListTile(
-            context: context,
             value: Config.mayFly,
             onChanged: setAllowFlyingAllowed,
             titleString: S.of(context).mayFly,
@@ -173,17 +160,14 @@ class _RuleSettingsPageState extends State<RuleSettingsPage> {
       const SizedBox(height: AppTheme.sizedBoxHeight),
       Text(S.of(context).removing, style: AppTheme.settingsHeaderStyle),
       SettingsCard(
-        context: context,
         children: <Widget>[
           SettingsSwitchListTile(
-            context: context,
             value: Config.mayRemoveFromMillsAlways,
             onChanged: setAllowRemovePieceInMill,
             titleString: S.of(context).mayRemoveFromMillsAlways,
             subtitleString: S.of(context).mayRemoveFromMillsAlways_Detail,
           ),
           SettingsSwitchListTile(
-            context: context,
             value: Config.mayRemoveMultiple,
             onChanged: setAllowRemoveMultiPiecesWhenCloseMultiMill,
             titleString: S.of(context).mayRemoveMultiple,

src/ui/flutter_app/lib/screens/settings/settings_card.dart

@@ -23,11 +23,9 @@ import 'package:sanmill/shared/theme/app_theme.dart';
 class SettingsCard extends StatelessWidget {
   const SettingsCard({
     Key? key,
-    required this.context,
     required this.children,
   }) : super(key: key);
 
-  final BuildContext context;
   final List<Widget> children;
 
   @override

src/ui/flutter_app/lib/screens/settings/settings_list_tile.dart

@@ -63,9 +63,7 @@ class SettingsListTile extends StatelessWidget {
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           Text(
-            trailingColor == null
-                ? (trailingString == null ? "" : trailingString!)
-                : trailingColor!.toRadixString(16),
+            trailingColor?.toRadixString(16) ?? trailingString ?? '',
             style: TextStyle(
               fontSize: Config.fontSize,
               backgroundColor:

src/ui/flutter_app/lib/screens/settings/settings_switch_list_tile.dart

@@ -23,14 +23,12 @@ import 'package:sanmill/shared/theme/app_theme.dart';
 class SettingsSwitchListTile extends StatelessWidget {
   const SettingsSwitchListTile({
     Key? key,
-    required this.context,
     required this.value,
     required this.onChanged,
     required this.titleString,
     this.subtitleString,
   }) : super(key: key);
 
-  final BuildContext context;
   final bool value;
   final String titleString;
   final String? subtitleString;

src/ui/flutter_app/lib/shared/common/config.dart

@@ -60,7 +60,7 @@ class Config {
   static double boardInnerLineWidth = 2.0;
   static double pieceWidth = 0.9;
   static double fontSize = 16.0;
-  static double boardTop = isLargeScreen() ? 75.0 : 36.0;
+  static double boardTop = isLargeScreen ? 75.0 : 36.0;
   static double animationDuration = 0.0;
 
   // Color
@@ -146,14 +146,14 @@ class Config {
     Config.isHistoryNavigationToolbarShown =
         settings['IsHistoryNavigationToolbarShown'] as bool? ?? false;
     Config.boardBorderLineWidth =
-        settings['BoardBorderLineWidth'] as double? ?? 2;
+        settings['BoardBorderLineWidth'] as double? ?? 2.0;
     Config.boardInnerLineWidth =
-        settings['BoardInnerLineWidth'] as double? ?? 2;
+        settings['BoardInnerLineWidth'] as double? ?? 2.0;
     Config.pieceWidth = settings['PieceWidth'] as double? ?? 0.9;
     Config.fontSize = settings['FontSize'] as double? ?? 16.0;
     Config.boardTop =
-        settings['BoardTop'] as double? ?? (isLargeScreen() ? 75 : 36);
-    Config.animationDuration = settings['AnimationDuration'] as double? ?? 0;
+        settings['BoardTop'] as double? ?? (isLargeScreen ? 75.0 : 36.0);
+    Config.animationDuration = settings['AnimationDuration'] as double? ?? 0.0;
 
     // Color
     Config.boardLineColor =

src/ui/flutter_app/lib/shared/common/constants.dart

@@ -78,10 +78,6 @@ class Constants {
   static final windowAspectRatio = windowHeight / windowWidth;
 }
 
-bool isSmallScreen() {
-  return Constants.windowHeight <= 800;
-}
+bool get isSmallScreen => Constants.windowHeight <= 800;
 
-bool isLargeScreen() {
-  return !isSmallScreen();
-}
+bool get isLargeScreen => !isSmallScreen;

src/ui/flutter_app/lib/shared/dialog.dart

@@ -189,9 +189,7 @@ Future<void> showPrivacyDialog(
               setPrivacyPolicyAccepted(false);
               SystemChannels.platform.invokeMethod('SystemNavigator.pop');
             },
-          )
-        else
-          const SizedBox(height: 0.0, width: 0.0),
+          ),
       ],
     ),
   );

src/ui/flutter_app/lib/shared/theme/app_theme.dart

@@ -4,7 +4,8 @@ import 'package:sanmill/shared/common/constants.dart';
 import 'package:sanmill/shared/theme/colors.dart';
 
 class AppTheme {
-  AppTheme._();
+  const AppTheme._();
+  // TODO: restructure theming. Some theme Elements should be accessed via Theme.of(context)
 
   // Theme data
   static final lightThemeData = ThemeData(
@@ -121,7 +122,7 @@ class AppTheme {
     color: moveHistoryTextColor,
   );
 
-  static double boardTop = isLargeScreen() ? 75.0 : 36.0;
+  static double boardTop = isLargeScreen ? 75.0 : 36.0;
   static double boardMargin = 10.0;
   static double boardScreenPaddingH = 10.0;
   static double boardBorderRadius = 5.0;

src/ui/flutter_app/pubspec.yaml

@@ -39,7 +39,7 @@ dev_dependencies:
   flutter_oss_licenses: ^1.0.1
   flutter_test:
     sdk: flutter
-  lint: ^1.0.0
+  lint: ^1.7.2
   msix: ^2.1.3
 
 flutter: