refactor

lib/preferences.dart

@@ -0,0 +1,20 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+class SharedPreferencesService {
+  static final SharedPreferencesService _instance = SharedPreferencesService._internal();
+  factory SharedPreferencesService() => _instance;
+  SharedPreferencesService._internal();
+
+  Future<void> initialize() async {
+    _prefs = await SharedPreferences.getInstance();
+  }
+
+  late SharedPreferences _prefs;
+
+  bool getBool(String key, bool defaultValue) => _prefs.getBool(key) ?? defaultValue;
+  Future<void> setBool(String key, bool value) => _prefs.setBool(key, value);
+  int? getInt(String key) => _prefs.getInt(key);
+  Future<void> setInt(String key, int value) => _prefs.setInt(key, value);
+  String? getString(String key) => _prefs.getString(key);
+  Future<void> setString(String key, String value) => _prefs.setString(key, value);
+}