我有一张由远程服务器管理的图像专辑.我想为用户提供下载相册的选项,并将其存储到照片中的自定义相册中.但由于专辑是动态的(照片被添加到其中),用户可以多次下载.我不想多次下载相同的图片,只有新的.
当我将图像存储在Photo应用程序中时,是否可以关联一些元数据(唯一ID)？然后检查该图像是否已存在？
我正在使用照片框架来创建自定义相册并保存照片.
编辑:这是我创建自定义相册和保存照片的代码
/** Returns the first album from the photos app with the specified name. */
static func getAlbumWithName(name: String, completion: (album: PHAssetCollection?) -> Void) {
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "localizedTitle = %@", name)
let fetchResult = PHAssetCollection.fetchAssetCollectionsWithType(PHAssetCollectionType.Album, subtype: PHAssetCollectionSubtype.Any, options: fetchOptions)
if fetchResult.count > 0 {
guard let album = fetchResult.firstObject as? PHAssetCollection else {return}
completion(album: album)
} else {
PHPhotoLibrary.sharedPhotoLibrary().performChanges({
PHAssetCollectionChangeRequest.creationRequestForAssetCollectionWithTitle(name)
}, completionHandler: { (result, error) in
if result {
FileUtils.getAlbumWithName(name, completion: completion) …