Refactor code to improve variable declarations by removing redundant types and enhancing readability across multiple files

Author: TechAurelian

analysis_options.yaml

@@ -2,11 +2,19 @@ include: package:flutter_lints/flutter.yaml
 
 linter:
   rules:
-    - prefer_const_declarations
+    - avoid_final_parameters
+    - omit_local_variable_types
+    - omit_obvious_local_variable_types
+    - parameter_assignments
     - prefer_const_constructors
+    - prefer_const_declarations
     - prefer_const_literals_to_create_immutables
-    - unnecessary_const
+    - prefer_final_fields
+    - prefer_final_in_for_each
+    - prefer_final_locals
     - prefer_single_quotes
+    - unnecessary_const
+    - unnecessary_nullable_for_final_variable_declarations
 
 formatter:
   page_width: 100

lib/common/app_settings.dart

@@ -16,17 +16,17 @@ class AppSettings {
     _saveCounterTapMode();
   }
 
-  static const String _counterTapModeKey = 'counterTapMode';
+  static const _counterTapModeKey = 'counterTapMode';
 
   /// Saves the counter tap mode to persistent storage.
   Future<void> _saveCounterTapMode() async {
-    SharedPreferences preferences = await SharedPreferences.getInstance();
+    final preferences = await SharedPreferences.getInstance();
     await preferences.setBool(_counterTapModeKey, _counterTapMode);
   }
 
   /// Loads app settings from persistent storage.
   Future<void> load() async {
-    SharedPreferences preferences = await SharedPreferences.getInstance();
+    final preferences = await SharedPreferences.getInstance();
     _counterTapMode = preferences.getBool(_counterTapModeKey) ?? false;
   }
 }

lib/common/strings.dart

@@ -9,51 +9,51 @@ library;
 
 import '../screens/home_screen.dart';
 
-const String appName = 'Hello World Counters';
+const appName = 'Hello World Counters';
 
 // -----------------------------------------------------------------------------
 // App Drawer
 // -----------------------------------------------------------------------------
 
 const String drawerTitle = appName;
-const String settingsItemTitle = 'Settings';
-const String aboutItemTitle = 'About this Hello World app';
-const String starAppItemTitle = 'Star on GitHub';
-const String rateAppItemTitle = 'Rate app';
+const settingsItemTitle = 'Settings';
+const aboutItemTitle = 'About this Hello World app';
+const starAppItemTitle = 'Star on GitHub';
+const rateAppItemTitle = 'Rate app';
 
 const Map<MenuAction, String> menuActions = {
   MenuAction.reset: 'Reset counter',
   MenuAction.share: 'Share...',
 };
 
-const String resetConfirm = 'Reset counter to zero?';
-const String resetConfirmReset = 'Reset';
-const String resetConfirmCancel = 'Cancel';
+const resetConfirm = 'Reset counter to zero?';
+const resetConfirmReset = 'Reset';
+const resetConfirmCancel = 'Cancel';
 
 String shareText(String name, String value) => 'The $name is $value';
 
 // -----------------------------------------------------------------------------
 // Home Screen - Main
 // -----------------------------------------------------------------------------
 
-const String incrementTooltip = 'Increment';
-const String decrementTooltip = 'Decrement';
+const incrementTooltip = 'Increment';
+const decrementTooltip = 'Decrement';
 
 // -----------------------------------------------------------------------------
 // Inspiration Screen
 // -----------------------------------------------------------------------------
 
 String inspirationScreenTitle(String name) => '$name Inspiration';
-const String inspirationHeader = 'Running out of ideas? Try counting these:';
+const inspirationHeader = 'Running out of ideas? Try counting these:';
 String noInspirationTitle(String name) => 'No inspiration ideas yet for $name.';
-const String noInspirationSubtitle = 'Use this counter for anything you\'d like!';
-const String ideaCopied = 'Idea copied to clipboard!';
-const String ideaCopyTooltip = 'Tap to copy idea';
+const noInspirationSubtitle = 'Use this counter for anything you\'d like!';
+const ideaCopied = 'Idea copied to clipboard!';
+const ideaCopyTooltip = 'Tap to copy idea';
 
 // -----------------------------------------------------------------------------
 // Settings Screen
 // -----------------------------------------------------------------------------
 
-const String settingsTitle = 'Settings';
-const String counterTapModeTitle = 'Counter tap mode';
-const String counterTapModeSubtitle = 'Tap anywhere to increase counter';
+const settingsTitle = 'Settings';
+const counterTapModeTitle = 'Counter tap mode';
+const counterTapModeSubtitle = 'Tap anywhere to increase counter';

lib/common/urls.dart

@@ -8,10 +8,10 @@
 library;
 
 /// The app's home page URL.
-const String aboutUrl = 'https://www.thehelloworldwriter.com/helloworldcounters/';
+const aboutUrl = 'https://www.thehelloworldwriter.com/helloworldcounters/';
 
 /// The URL to the source code repository of the app.
-const String starAppUrl = 'https://github.com/TheHelloWorldWriter/hello_world_counters';
+const starAppUrl = 'https://github.com/TheHelloWorldWriter/hello_world_counters';
 
 /// The URL for rating the app (a redirect).
-const String rateAppUrl = 'https://www.thehelloworldwriter.com/helloworldcounters/rate/';
+const rateAppUrl = 'https://www.thehelloworldwriter.com/helloworldcounters/rate/';

lib/models/counter.dart

@@ -48,7 +48,7 @@ class Counter {
 
   /// Saves the counter value to persistent storage.
   Future<void> _saveValue() async {
-    SharedPreferences preferences = await SharedPreferences.getInstance();
+    final preferences = await SharedPreferences.getInstance();
     await preferences.setInt(_counterKey(type), value);
   }
 
@@ -71,7 +71,7 @@ class Counter {
 
   /// Returns the name of the specified counter type (e.g. "Black Counter").
   static String nameOf(CounterType type) {
-    final String name = type.name;
+    final name = type.name;
     return '${name[0].toUpperCase()}${name.substring(1).toLowerCase()} Counter';
   }
 
@@ -95,16 +95,16 @@ class Counter {
 class Counters {
   /// Creates a Counters instance and creates the counter instances for all counter types.
   Counters() {
-    for (var type in CounterType.values) {
+    for (final type in CounterType.values) {
       _counters[type] = Counter(type);
     }
   }
 
   /// The persistent storage key where to keep the current counter type.
-  static const String currentCounterKey = 'current_counter';
+  static const currentCounterKey = 'current_counter';
 
   /// A map of counters for each counter type.
-  final Map<CounterType, Counter> _counters = <CounterType, Counter>{};
+  final _counters = <CounterType, Counter>{};
 
   /// The current counter type.
   CounterType _currentType = CounterType.blue;
@@ -123,20 +123,20 @@ class Counters {
 
   /// Saves the current counter type to persistent storage.
   Future<void> _saveCurrentType() async {
-    SharedPreferences preferences = await SharedPreferences.getInstance();
+    final preferences = await SharedPreferences.getInstance();
     await preferences.setInt(currentCounterKey, _currentType.index);
   }
 
   /// Loads counter states from persistent storage.
   Future<void> load() async {
-    SharedPreferences preferences = await SharedPreferences.getInstance();
+    final preferences = await SharedPreferences.getInstance();
 
     /// Load the current counter type, or set the default Blue counter
-    final int counterIndex = preferences.getInt(currentCounterKey) ?? CounterType.blue.index;
+    final counterIndex = preferences.getInt(currentCounterKey) ?? CounterType.blue.index;
     _currentType = CounterType.values[counterIndex];
 
     /// Loads the values of all counters
-    for (var counterType in _counters.keys) {
+    for (final counterType in _counters.keys) {
       _counters[counterType]?.loadValue(preferences);
     }
   }

lib/screens/home_screen.dart

@@ -34,10 +34,10 @@ class HomeScreen extends StatefulWidget {
 /// The logic and internal state for the app home screen widget.
 class _HomeScreenState extends State<HomeScreen> {
   /// The map of counters for each counter type.
-  final Counters _counters = Counters();
+  final _counters = Counters();
 
   /// The current app settings.
-  final AppSettings _appSettings = AppSettings();
+  final _appSettings = AppSettings();
 
   @override
   void initState() {
@@ -73,8 +73,8 @@ class _HomeScreenState extends State<HomeScreen> {
         break;
       case MenuAction.share:
         // Share the current counter value using the platform's share sheet.
-        final String name = _counters.current.name;
-        final String value = toDecimalString(context, _counters.current.value);
+        final name = _counters.current.name;
+        final value = toDecimalString(context, _counters.current.value);
         SharePlus.instance.share(ShareParams(text: strings.shareText(name, value), subject: name));
         break;
     }
@@ -114,10 +114,10 @@ class _HomeScreenState extends State<HomeScreen> {
 
   @override
   Widget build(BuildContext context) {
-    final bool isPortrait = MediaQuery.of(context).size.height >= 500;
-    final bool isLargeScreen = MediaQuery.of(context).size.longestSide >= 1024;
+    final isPortrait = MediaQuery.of(context).size.height >= 500;
+    final isLargeScreen = MediaQuery.of(context).size.longestSide >= 1024;
 
-    final CounterDisplay counterDisplay = CounterDisplay(
+    final counterDisplay = CounterDisplay(
       value: _counters.current.value,
       color: _counters.current.color,
       isPortrait: isPortrait,

lib/screens/inspiration_screen.dart

@@ -37,9 +37,9 @@ class _InspirationScreenState extends State<InspirationScreen> {
 
   @override
   Widget build(BuildContext context) {
-    final Color counterColor = widget.counter.color;
-    final Color textColor = counterColor.contrastOf();
-    final String colorName =
+    final counterColor = widget.counter.color;
+    final textColor = counterColor.contrastOf();
+    final colorName =
         widget.counter.type.name[0].toUpperCase() + widget.counter.type.name.substring(1);
 
     return Scaffold(

lib/screens/settings_screen.dart

@@ -28,7 +28,7 @@ class SettingsScreen extends StatefulWidget {
 class _SettingsScreenState extends State<SettingsScreen> {
   @override
   Widget build(BuildContext context) {
-    final bool isLargeScreen = MediaQuery.of(context).size.width >= 800.0;
+    final isLargeScreen = MediaQuery.of(context).size.width >= 800.0;
 
     return Scaffold(
       appBar: AppBar(

lib/utils/utils.dart

@@ -11,7 +11,7 @@ import 'package:url_launcher/url_launcher.dart';
 
 /// Formats [number] as a decimal, inserting locale-appropriate thousands separators as necessary.
 String toDecimalString(BuildContext context, int number) {
-  final MaterialLocalizations localizations = MaterialLocalizations.of(context);
+  final localizations = MaterialLocalizations.of(context);
   return localizations.formatDecimal(number);
 }
 

lib/widgets/counter_display.dart

@@ -29,7 +29,7 @@ class CounterDisplay extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final TextStyle? counterStyle = isPortrait
+    final counterStyle = isPortrait
         ? Theme.of(context).textTheme.displayLarge
         : Theme.of(context).textTheme.displayMedium;