The signature for a block that Photos calls while downloading asset resource data from iCloud. Used by the
- iOS 9+
- macOS 10.15+
- Mac Catalyst 13.0+
- tvOS 10+
If you request an asset resource whose data is not on the local device, and you have enabled downloading with the
is property, Photos calls your block periodically to report progress.
The block takes a single parameter:
A floating-point value indicating the progress of the download. A value of
0indicates that the download has just started, and a value of
1indicates the download is complete.