Feature #120 #89 selective backup in app (#137)

mobile/lib/modules/backup/views/album_preview_page.dart

@@ -0,0 +1,84 @@
+import 'dart:typed_data';
+
+import 'package:auto_route/auto_route.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_hooks/flutter_hooks.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:immich_mobile/shared/ui/immich_loading_indicator.dart';
+import 'package:photo_manager/photo_manager.dart';
+
+class AlbumPreviewPage extends HookConsumerWidget {
+  final AssetPathEntity album;
+  const AlbumPreviewPage({Key? key, required this.album}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final assets = useState<List<AssetEntity>>([]);
+
+    _getAssetsInAlbum() async {
+      assets.value = await album.getAssetListRange(start: 0, end: album.assetCount);
+    }
+
+    useEffect(() {
+      _getAssetsInAlbum();
+      return null;
+    }, []);
+
+    return Scaffold(
+      appBar: AppBar(
+        elevation: 0,
+        title: Column(
+          children: [
+            Text(
+              "${album.name} (${album.assetCount})",
+              style: const TextStyle(fontSize: 14, fontWeight: FontWeight.bold),
+            ),
+            Padding(
+              padding: const EdgeInsets.only(top: 4.0),
+              child: Text(
+                "ID ${album.id}",
+                style: TextStyle(fontSize: 10, color: Colors.grey[600], fontWeight: FontWeight.bold),
+              ),
+            ),
+          ],
+        ),
+        leading: IconButton(
+          onPressed: () => AutoRouter.of(context).pop(),
+          icon: const Icon(Icons.arrow_back_ios_new_rounded),
+        ),
+      ),
+      body: GridView.builder(
+        gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
+          crossAxisCount: 5,
+          crossAxisSpacing: 2,
+          mainAxisSpacing: 2,
+        ),
+        itemCount: assets.value.length,
+        itemBuilder: (context, index) {
+          Future<Uint8List?> thumbData =
+              assets.value[index].thumbnailDataWithSize(const ThumbnailSize(200, 200), quality: 50);
+
+          return FutureBuilder<Uint8List?>(
+            future: thumbData,
+            builder: ((context, snapshot) {
+              if (snapshot.hasData && snapshot.data != null) {
+                return Image.memory(
+                  snapshot.data!,
+                  width: 100,
+                  height: 100,
+                  fit: BoxFit.cover,
+                );
+              }
+
+              return const SizedBox(
+                width: 100,
+                height: 100,
+                child: ImmichLoadingIndicator(),
+              );
+            }),
+          );
+        },
+      ),
+    );
+  }
+}