Type Method


Returns a Boolean value that indicates whether the observed object supports automatic key-value observation for the given key.


class func automaticallyNotifiesObservers(forKey key: String) -> Bool

Return Value

true if the key-value observing machinery should automatically invoke willChangeValue(forKey:)/didChangeValue(forKey:) and willChange(_:valuesAt:forKey:)/didChange(_:valuesAt:forKey:) whenever instances of the class receive key-value coding messages for the key, or mutating key-value-coding-compliant methods for the key are invoked; otherwise false.


The default implementation returns true. Starting in OS X 10.5, the default implementation of this method searches the receiving class for a method whose name matches the pattern +automaticallyNotifiesObserversOf<Key>, and returns the result of invoking that method if it is found. Any found methods must return BOOL. If no such method is found true is returned.

See Also

Observing Customization

class func keyPathsForValuesAffectingValue(forKey: String) -> Set<String>

Returns a set of key paths for properties whose values affect the value of the specified key.

var observationInfo: UnsafeMutableRawPointer?

Returns a pointer that identifies information about all of the observers that are registered with the observed object.