Fix the new Material 3 app theme

+ Fix Flutter lint issues

lib/common/app_strings.dart

@@ -15,8 +15,8 @@ class AppStrings {
   static const String drawerTitle = appName;
   static const String settingsItemTitle = 'Settings';
   static const String helpItemTitle = 'Online Help';
-  static const String rateItemTitle = 'Rate or review';
-  static const String viewSourceItemTitle = 'View app source';
+  static const String rateItemTitle = 'Rate App';
+  static const String viewSourceItemTitle = 'View Source Code';
 
   static const Map<MenuAction, String> menuActions = {
     MenuAction.reset: 'Reset counter',

lib/main.dart

@@ -6,29 +6,32 @@ import 'package:flutter/material.dart';
 
 import 'common/app_strings.dart';
 import 'screens/home.dart';
-import 'utils/utils.dart';
 
 void main() {
   runApp(const CountersApp());
 }
 
 /// The app widget.
 class CountersApp extends StatelessWidget {
-  const CountersApp({Key? key}) : super(key: key);
+  const CountersApp({super.key});
 
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
       debugShowCheckedModeBanner: false,
       title: AppStrings.appName,
-      theme: ThemeData(
-        brightness: Brightness.light,
-        primarySwatch: Colors.white.createMaterialColor(),
-        textButtonTheme: TextButtonThemeData(
-          style: TextButton.styleFrom(foregroundColor: Colors.black),
+
+      // A black and white theme to go with the app's colored counters
+      theme: ThemeData.from(
+        colorScheme: ColorScheme.light(
+          primary: Colors.black,
+          surface: Colors.white,
+          onSurface: Colors.black,
+          surfaceTint: Colors.white,
+          primaryContainer: Colors.white,
+          onPrimaryContainer: Colors.black,
+          outlineVariant: Colors.grey.shade200,
         ),
-        visualDensity: VisualDensity.adaptivePlatformDensity,
-        typography: Typography.material2018(),
       ),
       home: const HomeScreen(),
     );

lib/models/counter.dart

@@ -2,9 +2,6 @@
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 // @author TechAurelian <[email protected]> (https://techaurelian.com)
 
-// cSpell:ignore endregion
-
-import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import 'package:shared_preferences/shared_preferences.dart';
@@ -17,8 +14,6 @@ class Counter {
   /// Creates a counter of the specified [type].
   Counter(this.type);
 
-  //#region Counter value
-
   /// The counter value.
   int _value = 0;
 
@@ -46,12 +41,8 @@ class Counter {
     _setValue(0);
   }
 
-  //#endregion
-
-  //#region Persistent storage
-
   /// Returns the persistent storage key for each counter type.
-  static String _counterKey(CounterType type) => '${describeEnum(type)}_counter';
+  static String _counterKey(CounterType type) => '${type.name}_counter';
 
   /// Saves the counter value to persistent storage.
   Future<void> _saveValue() async {
@@ -64,10 +55,6 @@ class Counter {
     _value = preferences.getInt(_counterKey(type)) ?? 0;
   }
 
-  //#endregion
-
-  //#region Counter type, color, name
-
   /// The counter type.
   final CounterType type;
 
@@ -82,8 +69,8 @@ class Counter {
 
   /// Returns the name of the specified counter type (e.g. "Black Counter").
   static String nameOf(CounterType type) {
-    final String name = describeEnum(type);
-    return '${name.substring(0, 1).toUpperCase()}${name.substring(1).toLowerCase()} Counter';
+    final String name = type.name;
+    return '${name[0].toUpperCase()}${name.substring(1).toLowerCase()} Counter';
   }
 
   /// A map with the corresponding [Color] value for each counter type.
@@ -100,8 +87,6 @@ class Counter {
     CounterType.orange: Colors.orange,
     CounterType.grey: Colors.grey,
   };
-
-//#endregion
 }
 
 /// Provides a map of counters for each counter type, and keeps a reference to the current counter.

lib/screens/home.dart

@@ -20,7 +20,7 @@ enum MenuAction { reset, share }
 
 /// The app home screen widget.
 class HomeScreen extends StatefulWidget {
-  const HomeScreen({Key? key}) : super(key: key);
+  const HomeScreen({super.key});
 
   @override
   State<HomeScreen> createState() => _HomeScreenState();

lib/screens/settings_screen.dart

@@ -9,9 +9,9 @@ import '../common/app_strings.dart';
 
 class SettingsScreen extends StatefulWidget {
   const SettingsScreen({
-    Key? key,
+    super.key,
     required this.appSettings,
-  }) : super(key: key);
+  });
 
   final AppSettings appSettings;
 

lib/utils/utils.dart

@@ -3,6 +3,7 @@
 // @author TechAurelian <[email protected]> (https://techaurelian.com)
 
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 
 import 'package:url_launcher/url_launcher.dart';
 
@@ -16,44 +17,27 @@ String toDecimalString(BuildContext context, int number) {
 ///
 /// Shows an error [SnackBar] if there is no support for launching the URL.
 Future<void> launchUrlExternal(BuildContext context, String url) async {
-  if (!await launchUrl(Uri.parse(url), mode: LaunchMode.externalApplication)) {
-    showSnackBar(context, 'Failed to open $url');
+  try {
+    await launchUrl(Uri.parse(url), mode: LaunchMode.externalApplication);
+  } on PlatformException catch (e) {
+    if (!context.mounted) return;
+    showSnackBar(context, 'Failed to open $url: ${e.message}');
   }
 }
 
 /// Shows a [SnackBar] with the specified [text] at the bottom of the specified scaffold.
 void showSnackBar(BuildContext context, String text) {
-  ScaffoldMessenger.of(context).showSnackBar(
-    SnackBar(
-      content: Text(text),
-    ),
-  );
+  ScaffoldMessenger.of(context)
+    ..removeCurrentSnackBar()
+    ..showSnackBar(SnackBar(content: Text(text)));
 }
 
 /// Utility Color extension methods.
 extension ColorX on Color {
   /// Returns the contrast color for this color.
-  Color contrastOf() =>
-      ThemeData.estimateBrightnessForColor(this) == Brightness.light ? Colors.black : Colors.white;
-
-  /// Creates a material color from any ARGB color value.
-  MaterialColor createMaterialColor() {
-    List<double> strengths = <double>[.05];
-    Map<int, Color> swatch = <int, Color>{};
-    final int r = red, g = green, b = blue;
-
-    for (int i = 1; i < 10; i++) {
-      strengths.add(0.1 * i);
-    }
-    for (var strength in strengths) {
-      final double ds = 0.5 - strength;
-      swatch[(strength * 1000).round()] = Color.fromRGBO(
-        r + ((ds < 0 ? r : (255 - r)) * ds).round(),
-        g + ((ds < 0 ? g : (255 - g)) * ds).round(),
-        b + ((ds < 0 ? b : (255 - b)) * ds).round(),
-        1,
-      );
-    }
-    return MaterialColor(value, swatch);
+  Color contrastOf() {
+    return ThemeData.estimateBrightnessForColor(this) == Brightness.light
+        ? Colors.black
+        : Colors.white;
   }
 }

lib/widgets/color_list_tile.dart

@@ -10,13 +10,13 @@ class ColorListTile extends StatelessWidget {
   ///
   /// The [color] and [title] parameters must not be null.
   const ColorListTile({
-    Key? key,
+    super.key,
     required this.color,
     required this.title,
     required this.subtitle,
     this.selected = false,
     this.onTap,
-  }) : super(key: key);
+  });
 
   /// The ARGB color value to fill the circular color swatch.
   final Color color;
@@ -43,10 +43,6 @@ class ColorListTile extends StatelessWidget {
           color: color,
           border: color == Colors.white ? Border.all() : null,
         ),
-        // title: Text(
-        //   title,
-        //   style: TextStyle(color: Theme.of(context).textTheme.bodyText1!.color),
-        // ),
         title: Text(title),
         subtitle: Text(subtitle),
         onTap: onTap,
@@ -61,12 +57,11 @@ class _ColorFilledCircle extends StatelessWidget {
   ///
   /// The [color] parameter must not be null.
   const _ColorFilledCircle({
-    Key? key,
+    super.key, // ignore: unused_element
     required this.color,
-    // ignore: unused_element
-    this.diameter = 40.0,
+    this.diameter = 40.0, // ignore: unused_element
     this.border,
-  }) : super(key: key);
+  });
 
   /// The color with which to fill the circle.
   final Color color;

lib/widgets/counter_display.dart

@@ -10,11 +10,11 @@ import '../utils/utils.dart';
 class CounterDisplay extends StatelessWidget {
   /// Creates a counter display widget.
   const CounterDisplay({
-    Key? key,
+    super.key,
     required this.value,
     required this.color,
     this.isPortrait = true,
-  }) : super(key: key);
+  });
 
   /// The color with which to fill the counter container.
   final Color color;
@@ -27,8 +27,9 @@ class CounterDisplay extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final TextStyle? counterStyle =
-        isPortrait ? Theme.of(context).textTheme.headline1 : Theme.of(context).textTheme.headline2;
+    final TextStyle? counterStyle = isPortrait
+        ? Theme.of(context).textTheme.displayLarge
+        : Theme.of(context).textTheme.displayMedium;
 
     return Container(
       alignment: Alignment.center,

lib/widgets/counters_drawer.dart

@@ -16,12 +16,12 @@ enum DrawerExtraActions { settings, help, rate, viewSource }
 class CountersDrawer extends StatelessWidget {
   /// Creates a counters drawer widget.
   const CountersDrawer({
-    Key? key,
+    super.key,
     required this.title,
     required this.counters,
     required this.onSelected,
     this.onExtraSelected,
-  }) : super(key: key);
+  });
 
   /// The title of the drawer displayed in the drawer header.
   final String title;
@@ -63,7 +63,7 @@ class CountersDrawer extends StatelessWidget {
               onTap: () => _onExtraActionTap(context, DrawerExtraActions.help),
             ),
             ListTile(
-              leading: const Icon(Icons.code),
+              leading: const Icon(Icons.flutter_dash),
               title: const Text(AppStrings.viewSourceItemTitle),
               onTap: () => _onExtraActionTap(context, DrawerExtraActions.viewSource),
             ),
@@ -86,7 +86,7 @@ class CountersDrawer extends StatelessWidget {
       child: DrawerHeader(
         child: Text(
           title,
-          style: Theme.of(context).textTheme.headline6,
+          style: Theme.of(context).textTheme.titleLarge,
         ),
       ),
     );