Overridden by subclasses to substitute a new class during keyed unarchiving.
- iOS 2.0+
- macOS 10.2+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
The class to substitute for the receiver during keyed unarchiving.
During keyed unarchiving, instances of the receiver will be decoded as members of the returned class. This method overrides the results of the decoder’s class and instance name to class encoding tables.