getThumbnailFromPath method

@override Future<Uint8List?> getThumbnailFromPath(PathWrapper<AssetPathEntity> path)

Get the thumbnail from the first asset under the specific path entity. 获取指定路径下的第一个资源的缩略图数据

Implementation

@override
Future<Uint8List?> getThumbnailFromPath(
  PathWrapper<AssetPathEntity> path,
) async {
  if (requestType == RequestType.audio) {
    return null;
  }
  final int assetCount = path.assetCount ?? await path.path.assetCountAsync;
  if (assetCount == 0) {
    return null;
  }
  final List<AssetEntity> assets = await path.path.getAssetListRange(
    start: 0,
    end: 1,
  );
  if (assets.isEmpty) {
    return null;
  }
  final AssetEntity asset = assets.single;
  // Obtain the thumbnail only when the asset is image or video.
  if (asset.type != AssetType.image && asset.type != AssetType.video) {
    return null;
  }
  final Uint8List? data = await asset.thumbnailDataWithSize(
    pathThumbnailSize,
  );
  final int index = _paths.indexWhere(
    (PathWrapper<AssetPathEntity> p) => p.path == path.path,
  );
  if (index != -1) {
    _paths[index] = _paths[index].copyWith(thumbnailData: data);
    notifyListeners();
  }
  return data;
}