Instance Method

addObserver:forKeyPath:options:context:

Raises an exception.

Declaration

- (void)addObserver:(NSObject *)observer forKeyPath:(NSString *)keyPath options:(NSKeyValueObservingOptions)options context:(void *)context;

Parameters

observer

The object to register for KVO notifications.

keyPath

The key path, relative to the array, of the property to observe. This value must not be nil.

options

A combination of NSKeyValueObservingOptions values that specifies what is included in observation notifications.

context

Arbitrary data that is passed to observer in observeValueForKeyPath:ofObject:change:context:.

Discussion

NSOrderedSet objects are not observable, so this method raises an exception when invoked on an NSOrderedSet object. Instead of observing an ordered set, observe the to-many relationship for which the ordered set is the collection of related objects.

See Also

Key-Value Observing Support