A description of changes that occurred in an asset or collection object.
- iOS 8+
- macOS 10.13+
- Mac Catalyst 13.0+
- tvOS 10.0+
PHObject object provides detailed information about differences between two states of an asset or collection object—one that you previously obtained and an updated state that would result if you fetched that entity again. You observe changes by adopting the
PHPhoto protocol and registering your observer with the shared
PHPhoto object. When Photos notifies your observer of a change, you get change details by passing the object you’re interested in to the
For an asset collection or collection list, a
PHObject object describe changes only to the collection’s properties. If you are instead interested in changes to the collection’s membership, fetch the collection’s contents and use the
change method to track changes to the fetch result.