A request to create, delete, or modify a Photos collection list, for use in a photo library change block.
SDKs
- iOS 8+
- macOS 10.15+
- Mac Catalyst 13.0+
- tvOS 10+
Framework
- Photos
Declaration
@interface PHCollectionListChangeRequest : PHChange Request
Overview
You use the PHCollection
class to request changes for PHCollection
objects. To make changes to collection lists (such as folders containing user-created albums) in the Photos library, create a change request using the appropriate class method for the change you want to perform.
Call the
creation
method to create a new asset collection.Request For Collection List With Title: Call the
delete
method to delete existing asset collections.Collection Lists: Call the
change
orRequest For Collection List: change
method to modify a collection’s metadata or its list of child collections.Request For Collection List: child Collections:
Before creating a change request, use the can
method to verify that the collection allows the edit operation you’re requesting. If you attempt to perform an unsupported edit operation, Photos throws an exception.
A change request for creating or modifying a collection list works like a mutable version of the collection list object. Use the change request’s properties and instance methods to request changes to the collection list itself. For example, the following code removes an album from a folder:
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
PHCollectionListChangeRequest *request = [PHCollectionListChangeRequest
changeRequestForCollectionList:self.myFolder
childCollections:self.folderContentsFetchResult];
[request removeChildCollections:@[ album ]];
} completionHandler:^(BOOL success, NSError *error) {
NSLog(@"Finished removing album from the folder. %@", (success ? @"Success" : error));
}];
After Photos runs the change block and calls your completion handler, the collection list’s state reflects the changes you requested in the block.
If you create or use a change request object outside a photo library change block, Photos raises an Objective-C exception. For details on change blocks, see PHPhoto
.