Raises an exception.
- iOS 5.0+
- macOS 10.7+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
The object to register for KVO notifications.
The key path, relative to the array, of the property to observe. This value must not be nil.
A combination of
NSKeyvalues that specifies what is included in observation notifications.
Value Observing Options
Arbitrary data that is passed to observer in
Value(for Key Path: of: change: context:)
NSOrdered objects are not observable, so this method raises an exception when invoked on an
NSOrdered object. Instead of observing an ordered set, observe the to-many relationship for which the ordered set is the collection of related objects.