added sqlite and hive as local storage options to todo-app

lib/main.dart

@@ -1,20 +1,33 @@
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
-import 'package:shared_preferences/shared_preferences.dart';
+import 'package:hive_flutter/hive_flutter.dart';
 import 'providers/todo_provider.dart';
 import 'screens/todo_list_screen.dart';
+import 'storage/hive_todo_storage.dart';
+import 'storage/todo_storage.dart';
 
-void main() {
-  runApp(ToDoApp());
+void main() async {
+  WidgetsFlutterBinding.ensureInitialized();
+  await Hive.initFlutter();
+  await Hive.openBox('todoBox');
+
+  //choose preferred storage type here
+  final storage = HiveToDoStorage();
+
+  runApp(ToDoApp(storage: storage));
 }
 
 class ToDoApp extends StatelessWidget {
+  final ToDoStorage storage;
+
+  const ToDoApp({required this.storage});
+
   @override
   Widget build(BuildContext context) {
     return ChangeNotifierProvider(
-      create: (_) => ToDoProvider(),
+      create: (_) => ToDoProvider(storage),
       child: MaterialApp(
-        title: 'To-Do list',
+        title: 'To-Do List',
         theme: ThemeData(
           primarySwatch: Colors.green,
         ),

lib/models/todo.dart

@@ -2,7 +2,7 @@ class ToDo {
   String title;
   String? description;
   DateTime deadline;
-  String priority; // High, Medium, Low
+  String priority;
   bool isCompleted;
 
   ToDo({

lib/providers/todo_provider.dart

@@ -1,46 +1,53 @@
 import 'package:flutter/foundation.dart';
 import '../models/todo.dart';
+import '../storage/todo_storage.dart';
 
 class ToDoProvider with ChangeNotifier {
   List<ToDo> _todos = [];
+  final ToDoStorage storage;
+
+  ToDoProvider(this.storage) {
+    loadTasks();
+  }
 
   List<ToDo> get todos => _todos;
 
   void addTask(ToDo todo) {
     _todos.add(todo);
+    storage.addTask(todo);
     notifyListeners();
   }
 
   void removeTask(int index) {
+    storage.removeTask(index);
     _todos.removeAt(index);
     notifyListeners();
   }
 
   void toggleCompletion(int index) {
     _todos[index].isCompleted = !_todos[index].isCompleted;
+    storage.updateTask(index, _todos[index]);
+    notifyListeners();
+  }
+
+  Future<void> loadTasks() async {
+    _todos = await storage.fetchTasks();
     notifyListeners();
   }
 
-  // sorting logic for deadline
   void sortByDeadline() {
-    _todos.sort((a, b) {
-      if (a.deadline == null) return 1; // Tasks without deadline should come last
-      if (b.deadline == null) return -1;
-      return a.deadline!.compareTo(b.deadline!);
-    });
+    _todos.sort((a, b) => a.deadline.compareTo(b.deadline));
     notifyListeners();
   }
 
-  // sorting logic for priority
   void sortByPriority() {
     Map<String, int> priorityMap = {'High': 1, 'Medium': 2, 'Low': 3};
     _todos.sort((a, b) => priorityMap[a.priority]!.compareTo(priorityMap[b.priority]!));
     notifyListeners();
   }
 
-  // sorting logic for staus
   void sortByStatus() {
-    _todos.sort((a, b) => a.isCompleted ? 1 : -1); // Uncompleted first
+    _todos.sort((a, b) => a.isCompleted ? 1 : -1);
     notifyListeners();
   }
 }

lib/screens/todo_list_screen.dart

@@ -3,12 +3,22 @@ import 'package:provider/provider.dart';
 import '../providers/todo_provider.dart';
 import '../widgets/todo_form.dart';
 
-class ToDoListScreen extends StatelessWidget {
+class ToDoListScreen extends StatefulWidget {
+  @override
+  _ToDoListScreenState createState() => _ToDoListScreenState();
+}
+
+class _ToDoListScreenState extends State<ToDoListScreen> {
+  @override
+  void initState() {
+    super.initState();
+    Provider.of<ToDoProvider>(context, listen: false).loadTasks();
+  }
+
   @override
   Widget build(BuildContext context) {
     var todoProvider = Provider.of<ToDoProvider>(context);
 
-    // Helper function to format DateTime
     String formatDate(DateTime date) {
       return '${date.day.toString().padLeft(2, '0')}/${date.month.toString().padLeft(2, '0')}/${date.year}';
     }
@@ -17,7 +27,6 @@ class ToDoListScreen extends StatelessWidget {
       appBar: AppBar(
         title: Text('To-Do list'),
         actions: [
-          // Filter Dropdown Menü
           PopupMenuButton<String>(
             onSelected: (value) {
               switch (value) {

lib/storage/hive_todo_storage.dart

@@ -0,0 +1,35 @@
+import 'package:hive/hive.dart';
+import '../models/todo.dart';
+import 'todo_storage.dart';
+
+class HiveToDoStorage implements ToDoStorage {
+  static const String _boxName = 'todoBox';
+
+  Future<Box> get _box async {
+    return Hive.box(_boxName);
+  }
+
+  @override
+  Future<void> addTask(ToDo todo) async {
+    final box = await _box;
+    await box.add(todo.toJson());
+  }
+
+  @override
+  Future<void> removeTask(int index) async {
+    final box = await _box;
+    await box.deleteAt(index);
+  }
+
+  @override
+  Future<void> updateTask(int index, ToDo todo) async {
+    final box = await _box;
+    await box.putAt(index, todo.toJson());
+  }
+
+  @override
+  Future<List<ToDo>> fetchTasks() async {
+    final box = await _box;
+    return box.values.map((e) => ToDo.fromJson(Map<String, dynamic>.from(e))).toList();
+  }
+}

lib/storage/sqlite_todo_storage.dart

@@ -0,0 +1,68 @@
+import 'dart:async';
+import 'package:path/path.dart';
+import 'package:sqflite/sqflite.dart';
+import '../models/todo.dart';
+import 'todo_storage.dart';
+
+class SQLiteToDoStorage implements ToDoStorage {
+  Database? _database;
+
+  Future<Database> get database async {
+    if (_database != null) return _database!;
+    _database = await _initDatabase();
+    return _database!;
+  }
+
+  Future<Database> _initDatabase() async {
+    final path = join(await getDatabasesPath(), 'todo_database.db');
+    return openDatabase(
+      path,
+      onCreate: (db, version) {
+        return db.execute(
+          'CREATE TABLE todos(id INTEGER PRIMARY KEY, title TEXT, description TEXT, deadline TEXT, priority TEXT, isCompleted INTEGER)',
+        );
+      },
+      version: 1,
+    );
+  }
+
+  @override
+  Future<void> addTask(ToDo todo) async {
+    final db = await database;
+    await db.insert(
+      'todos',
+      todo.toJson(),
+      conflictAlgorithm: ConflictAlgorithm.replace,
+    );
+  }
+
+  @override
+  Future<void> removeTask(int index) async {
+    final db = await database;
+    await db.delete(
+      'todos',
+      where: 'id = ?',
+      whereArgs: [index],
+    );
+  }
+
+  @override
+  Future<void> updateTask(int index, ToDo todo) async {
+    final db = await database;
+    await db.update(
+      'todos',
+      todo.toJson(),
+      where: 'id = ?',
+      whereArgs: [index],
+    );
+  }
+
+  @override
+  Future<List<ToDo>> fetchTasks() async {
+    final db = await database;
+    final maps = await db.query('todos');
+    return List.generate(maps.length, (i) {
+      return ToDo.fromJson(maps[i]);
+    });
+  }
+}

lib/storage/todo_storage.dart

@@ -0,0 +1,8 @@
+import '../models/todo.dart';
+
+abstract class ToDoStorage {
+  Future<void> addTask(ToDo todo);
+  Future<void> removeTask(int index);
+  Future<void> updateTask(int index, ToDo todo);
+  Future<List<ToDo>> fetchTasks();
+}

lib/widgets/todo_form.dart

@@ -17,11 +17,11 @@ class _ToDoFormState extends State<ToDoForm> {
   bool get _isFormValid => _titleController.text.isNotEmpty && _selectedDate != null;
 
   void _submitForm() {
-    if (!_isFormValid) return; // Ensure the form is valid before submitting
+    if (!_isFormValid) return;
 
     var newTodo = ToDo(
       title: _titleController.text,
-      description: _descriptionController.text.trim().isEmpty ? '' : _descriptionController.text, // Korrektur hier
+      description: _descriptionController.text.trim().isEmpty ? '' : _descriptionController.text,
       deadline: _selectedDate!,
       priority: _selectedPriority,
     );
@@ -45,10 +45,9 @@ class _ToDoFormState extends State<ToDoForm> {
               hintText: 'Enter task title',
             ),
             onChanged: (_) {
-              setState(() {}); // Trigger UI update when title changes
+              setState(() {});
             },
           ),
-          // Description input (optional)
           TextField(
             controller: _descriptionController,
             decoration: InputDecoration(
@@ -81,7 +80,7 @@ class _ToDoFormState extends State<ToDoForm> {
               Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
-                  Text('Priority'), // Label for Priority
+                  Text('Priority'),
                   DropdownButton<String>(
                     value: _selectedPriority,
                     onChanged: (newValue) {
@@ -115,7 +114,7 @@ class _ToDoFormState extends State<ToDoForm> {
                 style: ButtonStyle(
                   backgroundColor: MaterialStateProperty.resolveWith<Color>(
                         (Set<MaterialState> states) {
-                      return _isFormValid ? Colors.blue : Colors.grey; // Button enabled only if form is valid
+                      return _isFormValid ? Colors.blue : Colors.grey;
                     },
                   ),
                 ),

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -5,8 +5,12 @@
 import FlutterMacOS
 import Foundation
 
+import path_provider_foundation
 import shared_preferences_foundation
+import sqflite_darwin
 
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
+  PathProviderPlugin.register(with: registry.registrar(forPlugin: "PathProviderPlugin"))
   SharedPreferencesPlugin.register(with: registry.registrar(forPlugin: "SharedPreferencesPlugin"))
+  SqflitePlugin.register(with: registry.registrar(forPlugin: "SqflitePlugin"))
 }

pubspec.lock

@@ -41,6 +41,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.18.0"
+  crypto:
+    dependency: transitive
+    description:
+      name: crypto
+      sha256: "1e445881f28f22d6140f181e07737b22f1e099a5e1ff94b0af2f9e4a463f4855"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.6"
   cupertino_icons:
     dependency: "direct main"
     description:
@@ -96,6 +104,22 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  hive:
+    dependency: "direct main"
+    description:
+      name: hive
+      sha256: "8dcf6db979d7933da8217edcec84e9df1bdb4e4edc7fc77dbd5aa74356d6d941"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.3"
+  hive_flutter:
+    dependency: "direct main"
+    description:
+      name: hive_flutter
+      sha256: dca1da446b1d808a51689fb5d0c6c9510c0a2ba01e22805d492c73b68e33eecc
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
   leak_tracker:
     dependency: transitive
     description:
@@ -161,13 +185,37 @@ packages:
     source: hosted
     version: "1.0.0"
   path:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: path
       sha256: "087ce49c3f0dc39180befefc60fdb4acd8f8620e5682fe2476afd0b3688bb4af"
       url: "https://pub.dev"
     source: hosted
     version: "1.9.0"
+  path_provider:
+    dependency: transitive
+    description:
+      name: path_provider
+      sha256: fec0d61223fba3154d87759e3cc27fe2c8dc498f6386c6d6fc80d1afdd1bf378
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.4"
+  path_provider_android:
+    dependency: transitive
+    description:
+      name: path_provider_android
+      sha256: c464428172cb986b758c6d1724c603097febb8fb855aa265aeecc9280c294d4a
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.12"
+  path_provider_foundation:
+    dependency: transitive
+    description:
+      name: path_provider_foundation
+      sha256: f234384a3fdd67f989b4d54a5d73ca2a6c422fa55ae694381ae0f4375cd1ea16
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.0"
   path_provider_linux:
     dependency: transitive
     description:
@@ -285,6 +333,46 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.10.0"
+  sqflite:
+    dependency: "direct main"
+    description:
+      name: sqflite
+      sha256: "79a297dc3cc137e758c6a4baf83342b039e5a6d2436fcdf3f96a00adaaf2ad62"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.0"
+  sqflite_android:
+    dependency: transitive
+    description:
+      name: sqflite_android
+      sha256: "78f489aab276260cdd26676d2169446c7ecd3484bbd5fead4ca14f3ed4dd9ee3"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.0"
+  sqflite_common:
+    dependency: transitive
+    description:
+      name: sqflite_common
+      sha256: "4468b24876d673418a7b7147e5a08a715b4998a7ae69227acafaab762e0e5490"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.4+5"
+  sqflite_darwin:
+    dependency: transitive
+    description:
+      name: sqflite_darwin
+      sha256: "769733dddf94622d5541c73e4ddc6aa7b252d865285914b6fcd54a63c4b4f027"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1-1"
+  sqflite_platform_interface:
+    dependency: transitive
+    description:
+      name: sqflite_platform_interface
+      sha256: "8dd4515c7bdcae0a785b0062859336de775e8c65db81ae33dd5445f35be61920"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.0"
   stack_trace:
     dependency: transitive
     description:
@@ -309,6 +397,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.2.0"
+  synchronized:
+    dependency: transitive
+    description:
+      name: synchronized
+      sha256: "69fe30f3a8b04a0be0c15ae6490fc859a78ef4c43ae2dd5e8a623d45bfcf9225"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.3.0+3"
   term_glyph:
     dependency: transitive
     description:
@@ -325,6 +421,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.7.2"
+  typed_data:
+    dependency: transitive
+    description:
+      name: typed_data
+      sha256: f9049c039ebfeb4cf7a7104a675823cd72dba8297f264b6637062516699fa006
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.0"
   vector_math:
     dependency: transitive
     description:

pubspec.yaml

@@ -34,6 +34,12 @@ dependencies:
   provider: ^6.0.0
   shared_preferences: ^2.0.0
   
+  # local storage dependencies
+  sqflite: ^2.0.0+4
+  path: ^1.8.0
+  hive: ^2.0.0
+  hive_flutter: ^1.1.0
+
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.