使用Apple IOS Photokit对共享相册进行排序

Question

Before I do a lot of fruitless experimenting, does anyone know if you can sort shared albums using the Apple Photokit. I know the native photos app is not able to.

Answer 1

As far i understand from your question, you want to sort based on the timestamp at which asset was added. Try this:

_assets = [[NSArray alloc] init];

PHFetchOptions *options = [[PHFetchOptions alloc] init];
//Sort according to date
options.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"creationDate" ascending:NO]];
//If you want just images
options.predicate = [NSPredicate predicateWithFormat:@"mediaType == %d", PHAssetMediaTypeImage];
//Each album is an assetCollection
PHFetchResult *fetchResult = [PHAsset fetchAssetsInAssetCollection:self.assetsCollection options:options];
_assets = fetchResult;

Answer 2

You can sort by any PHAsset key (mediaType, duration, etc).

_assets = [[NSArray alloc] init];
PHFetchOptions *options = [[PHFetchOptions alloc] init];
//Sort according to date
options.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"{PHAsset.key}" ascending:NO]];
//For example
options.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"mediaType" ascending:NO]];
//If you want just images
options.predicate = [NSPredicate predicateWithFormat:@"mediaType == %d", PHAssetMediaTypeImage];
//If you want just videos
options.predicate = [NSPredicate predicateWithFormat:@"mediaType == %d", PHAssetMediaTypeImage];
//If you want both videos and photos
// leave predicate as-is
//Each album is an assetCollection
PHFetchResult *fetchResult = [PHAsset fetchAssetsInAssetCollection:self.assetsCollection options:options];
_assets = fetchResult;

So, you can do the same for albums or PHAssetCollections:

 let options = PHFetchOptions()
//Sort according to date
options.sortDescriptors = [NSSortDescriptor(@"{PHAssetCollection.key}" ascending:true]
//Query collection with sort descriptor
let result:PHFetchResult = PHAssetCollection.fetchAssetCollectionsWithType(PHAssetCollectionType.Album, subtype: PHAssetCollectionSubtype.AlbumCloudShared, options: nil)