added persistence using shared preferences

android/app/proguard-rules.pro

@@ -0,0 +1,2 @@
+-keep class io.flutter.plugins.sharedpreferences.** { *; }
+-keep class io.flutter.plugins.sharedpreferences.LegacySharedPreferencesPlugin { *; }

android/app/src/main/kotlin/com/example/maps_bookmarks/MainActivity.kt

@@ -5,6 +5,7 @@ import android.os.Bundle
 import io.flutter.embedding.android.FlutterActivity
 import io.flutter.embedding.engine.FlutterEngine
 import io.flutter.plugin.common.MethodChannel
+import io.flutter.plugins.sharedpreferences.SharedPreferencesPlugin
 
 class MainActivity: FlutterActivity() {
     private var sharedText: String? = null
@@ -31,6 +32,8 @@ class MainActivity: FlutterActivity() {
     }
 
     override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
+        super.configureFlutterEngine(flutterEngine)
+        flutterEngine.plugins.add(SharedPreferencesPlugin())
         MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL)
             .setMethodCallHandler { call, result ->
                 if (call.method == "getSharedText") {

devtools_options.yaml

@@ -0,0 +1,3 @@
+description: This file stores settings for Dart & Flutter DevTools.
+documentation: https://docs.flutter.dev/tools/devtools/extensions#configure-extension-enablement-states
+extensions:

lib/main.dart

@@ -1,7 +1,10 @@
 import 'package:flutter/material.dart';
 import 'pages/collections_page.dart';
+import 'service/storage.dart';
 
-void main() {
+void main() async {
+  WidgetsFlutterBinding.ensureInitialized();
+  await Storage.initialize();
   runApp(const MapsBookmarks());
 }
 

lib/model/bookmark.dart

@@ -1,11 +1,35 @@
 class Bookmark {
-  Bookmark({required this.name, required this.link});
+  Bookmark({
+    required this.collectionId,
+    required this.name,
+    required this.link,
+    required this.description,
+    int? createdAt,
+  }) : createdAt = createdAt ?? DateTime.now().millisecondsSinceEpoch;
 
-  factory Bookmark.fromJson(Map<String, dynamic> json) =>
+  factory Bookmark.fromJson(Map<String, dynamic> json) => Bookmark(
-      Bookmark(name: json['name'] as String, link: json['link'] as String);
+    collectionId: json['collectionId'] as int,
+    name: json['name'] as String,
+    link: json['link'] as String,
+    description: json['description'] as String,
+    createdAt: json['createdAt'] as int,
+  );
 
+  int collectionId;
   String link;
   String name;
+  String description;
+  int createdAt;
 
-  Map<String, dynamic> toJson() => {'name': name, 'link': link};
+  int get id => createdAt;
+
+  DateTime get createdDate => DateTime.fromMillisecondsSinceEpoch(createdAt);
+
+  Map<String, dynamic> toJson() => {
+    'collectionId': collectionId,
+    'name': name,
+    'link': link,
+    'description': description,
+    'createdAt': createdAt,
+  };
 }

lib/model/collection.dart

@@ -1,10 +1,18 @@
 class Collection {
-  Collection({required this.name});
+  Collection({required this.name, int? createdAt})
+    : createdAt = createdAt ?? DateTime.now().millisecondsSinceEpoch;
 
-  factory Collection.fromJson(Map<String, dynamic> json) =>
+  factory Collection.fromJson(Map<String, dynamic> json) => Collection(
-      Collection(name: json['name'] as String);
+    name: json['name'] as String,
+    createdAt: json['createdAt'] as int,
+  );
 
   String name;
+  int createdAt; // used as Id with millisecondsSinceEpoch
 
-  Map<String, dynamic> toJson() => {'name': name};
+  int get id => createdAt;
+
+  DateTime get createdDate => DateTime.fromMillisecondsSinceEpoch(createdAt);
+
+  Map<String, dynamic> toJson() => {'name': name, 'createdAt': createdAt};
 }

lib/service/storage.dart

@@ -0,0 +1,117 @@
+import 'dart:convert' show jsonDecode, jsonEncode;
+
+import 'package:shared_preferences/shared_preferences.dart';
+
+import '../model/bookmark.dart';
+import '../model/collection.dart';
+
+class Storage {
+  static const String _collectionsKey = 'collections';
+  static const String _bookmarksKey = 'bookmarks';
+  static const String _statsKey = 'stats';
+  static SharedPreferencesWithCache? _prefsWithCache;
+
+  static Future<void> initialize() async {
+    _prefsWithCache = await SharedPreferencesWithCache.create(
+      cacheOptions: const SharedPreferencesWithCacheOptions(
+        allowList: <String>{_collectionsKey, _bookmarksKey, _statsKey},
+      ),
+    );
+  }
+
+  static SharedPreferencesWithCache get _prefs {
+    if (_prefsWithCache == null) {
+      throw StateError(
+        'BookmarkStorage not initialized. Call initialize() first.',
+      );
+    }
+    return _prefsWithCache!;
+  }
+
+  static List<Collection> loadCollections() {
+    final jsonString = _prefs.getString(_collectionsKey) ?? '[]';
+    final jsonList = jsonDecode(jsonString) as List;
+    return jsonList
+        .map((json) => Collection.fromJson(json as Map<String, dynamic>))
+        .toList();
+  }
+
+  static Future<void> saveCollections(List<Collection> collections) async {
+    final jsonList = collections.map((c) => c.toJson()).toList();
+    await _prefs.setString(_collectionsKey, jsonEncode(jsonList));
+  }
+
+  static List<Bookmark> loadAllBookmarks() {
+    final jsonString = _prefs.getString(_bookmarksKey) ?? '[]';
+    final jsonList = jsonDecode(jsonString) as List;
+    return jsonList
+        .map((json) => Bookmark.fromJson(json as Map<String, dynamic>))
+        .toList();
+  }
+
+  static Future<void> saveAllBookmarks(List<Bookmark> bookmarks) async {
+    final jsonList = bookmarks.map((b) => b.toJson()).toList();
+    await _prefs.setString(_bookmarksKey, jsonEncode(jsonList));
+  }
+
+  static List<Bookmark> loadBookmarksForCollection(int collectionId) {
+    final allBookmarks = loadAllBookmarks();
+    return allBookmarks.where((b) => b.collectionId == collectionId).toList();
+  }
+
+  static Future<void> addBookmark(Bookmark bookmark) async {
+    final bookmarks = loadAllBookmarks();
+    bookmarks.add(bookmark);
+    await saveAllBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteBookmarkById(int bookmarkId) async {
+    final bookmarks = loadAllBookmarks();
+    bookmarks.removeWhere((b) => b.id == bookmarkId);
+    await saveAllBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteBookmarksForCollection(int collectionId) async {
+    final bookmarks = loadAllBookmarks();
+    bookmarks.removeWhere((b) => b.collectionId == collectionId);
+    await saveAllBookmarks(bookmarks);
+  }
+
+  static Future<void> updateBookmarkById(
+    int bookmarkId, {
+    String? name,
+    String? description,
+  }) async {
+    final bookmarks = loadAllBookmarks();
+    final index = bookmarks.indexWhere((b) => b.id == bookmarkId);
+
+    if (index == -1) return;
+
+    if (name != null) bookmarks[index].name = name;
+    if (description != null) bookmarks[index].description = description;
+
+    await saveAllBookmarks(bookmarks);
+  }
+
+  static Map<String, int> getStats() {
+    final statsJson = _prefs.getString(_statsKey) ?? '{}';
+    final stats = jsonDecode(statsJson) as Map<String, dynamic>;
+    return {
+      'totalCollections': stats['totalCollections'] ?? 0,
+      'totalBookmarks': stats['totalBookmarks'] ?? 0,
+    };
+  }
+
+  static Future<void> updateStats() async {
+    final collections = loadCollections();
+    final bookmarks = loadAllBookmarks();
+
+    final stats = {
+      'totalCollections': collections.length,
+      'totalBookmarks': bookmarks.length,
+      'lastUpdated': DateTime.now().millisecondsSinceEpoch,
+    };
+
+    await _prefs.setString(_statsKey, jsonEncode(stats));
+  }
+}

pubspec.lock

@@ -65,6 +65,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.3.3"
+  ffi:
+    dependency: transitive
+    description:
+      name: ffi
+      sha256: "289279317b4b16eb2bb7e271abccd4bf84ec9bdcbe999e278a94b804f5630418"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.4"
+  file:
+    dependency: transitive
+    description:
+      name: file
+      sha256: a3b4f84adafef897088c160faf7dfffb7696046cb13ae90b508c2cbc95d3b8d4
+      url: "https://pub.dev"
+    source: hosted
+    version: "7.0.1"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -74,15 +90,20 @@ packages:
     dependency: "direct dev"
     description:
       name: flutter_lints
-      sha256: "5398f14efa795ffb7a33e9b6a08798b26a180edac4ad7db3f231e40f82ce11e1"
+      sha256: "3105dc8492f6183fb076ccf1f351ac3d60564bff92e20bfc4af9cc1651f4e7e1"
       url: "https://pub.dev"
     source: hosted
-    version: "5.0.0"
+    version: "6.0.0"
   flutter_test:
     dependency: "direct dev"
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_web_plugins:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   leak_tracker:
     dependency: transitive
     description:
@@ -111,10 +132,10 @@ packages:
     dependency: transitive
     description:
       name: lints
-      sha256: c35bb79562d980e9a453fc715854e1ed39e24e7d0297a880ef54e17f9874a9d7
+      sha256: a5e2b223cb7c9c8efdc663ef484fdd95bb243bff242ef5b13e26883547fce9a0
       url: "https://pub.dev"
     source: hosted
-    version: "5.1.1"
+    version: "6.0.0"
   matcher:
     dependency: transitive
     description:
@@ -147,6 +168,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.9.1"
+  path_provider_linux:
+    dependency: transitive
+    description:
+      name: path_provider_linux
+      sha256: f7a1fe3a634fe7734c8d3f2766ad746ae2a2884abe22e241a8b301bf5cac3279
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.1"
+  path_provider_platform_interface:
+    dependency: transitive
+    description:
+      name: path_provider_platform_interface
+      sha256: "88f5779f72ba699763fa3a3b06aa4bf6de76c8e5de842cf6f29e2e06476c2334"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
+  path_provider_windows:
+    dependency: transitive
+    description:
+      name: path_provider_windows
+      sha256: bd6f00dbd873bfb70d0761682da2b3a2c2fccc2b9e84c495821639601d81afe7
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.0"
   platform:
     dependency: transitive
     description:
@@ -155,6 +200,70 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.1.6"
+  plugin_platform_interface:
+    dependency: transitive
+    description:
+      name: plugin_platform_interface
+      sha256: "4820fbfdb9478b1ebae27888254d445073732dae3d6ea81f0b7e06d5dedc3f02"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.8"
+  shared_preferences:
+    dependency: "direct main"
+    description:
+      name: shared_preferences
+      sha256: "6e8bf70b7fef813df4e9a36f658ac46d107db4b4cfe1048b477d4e453a8159f5"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.3"
+  shared_preferences_android:
+    dependency: transitive
+    description:
+      name: shared_preferences_android
+      sha256: a2608114b1ffdcbc9c120eb71a0e207c71da56202852d4aab8a5e30a82269e74
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.12"
+  shared_preferences_foundation:
+    dependency: transitive
+    description:
+      name: shared_preferences_foundation
+      sha256: "6a52cfcdaeac77cad8c97b539ff688ccfc458c007b4db12be584fbe5c0e49e03"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.4"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      sha256: "580abfd40f415611503cae30adf626e6656dfb2f0cee8f465ece7b6defb40f2f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      sha256: "57cbf196c486bc2cf1f02b85784932c6094376284b3ad5779d1b1c6c6a816b80"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      sha256: c49bd060261c9a3f0ff445892695d6212ff603ef3115edbb448509d407600019
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      sha256: "94ef0f72b2d71bc3e700e025db3710911bd51a71cefb65cc609dd0d9a982e3c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -224,6 +333,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "15.0.2"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: "868d88a33d8a87b18ffc05f9f030ba328ffefba92d6c127917a2ba740f9cfe4a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
+  xdg_directories:
+    dependency: transitive
+    description:
+      name: xdg_directories
+      sha256: "7a3f37b05d989967cdddcbb571f1ea834867ae2faa29725fd085180e0883aa15"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
 sdks:
   dart: ">=3.9.2 <4.0.0"
-  flutter: ">=3.18.0-18.0.pre.54"
+  flutter: ">=3.29.0"

pubspec.yaml

@@ -14,12 +14,13 @@ dependencies:
  
   cupertino_icons: ^1.0.8
   android_intent_plus: ^6.0.0
+  shared_preferences: ^2.3.2
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
 
-  flutter_lints: ^5.0.0
+  flutter_lints: ^6.0.0
 
 flutter: