An encoding method for subclasses to override to conditionally encode an object, preserving common references to it, only if it has been unconditionally encoded.
- iOS 2.0+
- macOS 10.2+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
Subclasses must override this method if they support keyed coding.
The encoded object is decoded with the
decodeObject(forKey:) method. If
objv was never encoded unconditionally,
nil in place of
Encoding General Data
An encoding method for subclasses to override to encode an interconnected group of objects, starting with the provided root object.