If specified, a notification should be sent to the observer immediately, before the observer registration method even returns.
SDKs
- iOS 2.0+
- macOS 10.5+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
Framework
- Foundation
Declaration
static var initial: NSKeyDiscussion
The change dictionary in the notification will always contain an new entry if new is also specified but will never contain an old entry. (In an initial notification the current value of the observed property may be old, but it's new to the observer.) You can use this option instead of explicitly invoking, at the same time, code that is also invoked by the observer's observe method. When this option is used withadd a notification will be sent for each indexed object to which the observer is being added.