removeObserver(_:fromObjectsAt:forKeyPath:context:)
Raises an exception.
Declaration
func removeObserver(_ observer: NSObject, fromObjectsAt indexes: IndexSet, forKeyPath keyPath: String, context: UnsafeMutableRawPointer?)Parameters
- observer:
The object to remove as an observer.
- indexes:
The index set.
- keyPath:
A key-path, relative to the array, for which
observeris registered to receive KVO change notifications. This value must not benil. - context:
The context passed to the notifications.
Discussion
NSArray objects are not observable, so this method raises an exception when invoked on an NSArray object. Instead of observing an array, observe the to-many relationship for which the array is the collection of related objects.