- iOS 4.0+
- macOS 10.6+
The methods in the
QLPreview protocol are also declared as a category on the
NSURL class. As a result, you can use
NSURL objects directly as preview items—provided that you want to use the default titles of those items. A default title is the last path component of an item’s URL. If you want to supply your own preview item titles, create your own preview item objects that adopt this protocol.