added bookmarks page

lib/main.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'pages/bookmarks_page.dart';
 import 'pages/collections_page.dart';
 import 'service/storage.dart';
 
@@ -18,7 +19,10 @@ class MapsBookmarks extends StatelessWidget {
         colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
       ),
       initialRoute: CollectionsPage.routeName,
-      routes: {CollectionsPage.routeName: (context) => const CollectionsPage()},
+      routes: {
+        CollectionsPage.routeName: (context) => const CollectionsPage(),
+        BookmarksPage.routeName: (context) => const BookmarksPage(),
+      },
     );
   }
 }

lib/pages/bookmarks_page.dart

@@ -0,0 +1,35 @@
+import 'package:flutter/material.dart';
+
+import '../service/bookmarks_provider.dart';
+import '../service/storage.dart';
+
+class BookmarksPage extends StatelessWidget {
+  const BookmarksPage({super.key});
+
+  static const String routeName = '/bookmarks';
+
+  @override
+  Widget build(BuildContext context) {
+    if (BookmarksProvider.selectedCollectionId == null) {
+      Navigator.of(context).pop();
+    }
+    final bookmarks = Storage.loadBookmarksForCollection(
+      BookmarksProvider.selectedCollectionId!,
+    );
+
+    BookmarksProvider.selectedCollectionId == null;
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(
+          Storage.loadCollections()
+              .firstWhere((c) => c.id == BookmarksProvider.selectedCollectionId)
+              .name,
+        ),
+      ),
+      body: ListView(
+        children: bookmarks.map((e) => ListTile(title: Text(e.name))).toList(),
+      ),
+    );
+  }
+}

lib/pages/collections_page.dart

@@ -1,8 +1,10 @@
 import 'package:flutter/material.dart';
 
 import '../model/collection.dart';
+import '../service/bookmarks_provider.dart';
 import '../service/storage.dart';
 import '../widgets/create_bookmark_collection_dialog.dart';
+import 'bookmarks_page.dart';
 
 class CollectionsPage extends StatefulWidget {
   const CollectionsPage({super.key});
@@ -43,6 +45,13 @@ class _CollectionsPageState extends State<CollectionsPage> {
   }
 
   Widget itemBuilder(BuildContext context, int index) {
-    return ListTile(title: Text(collections.elementAt(index).name));
+    final collection = collections.elementAt(index);
+    return ListTile(
+      title: Text(collection.name),
+      onTap: () {
+        BookmarksProvider.selectedCollectionId = collection.id;
+        Navigator.pushNamed(context, BookmarksPage.routeName);
+      },
+    );
   }
 }

lib/service/bookmarks_provider.dart

@@ -0,0 +1,3 @@
+class BookmarksProvider {
+  static int? selectedCollectionId;
+}