Instance Method

didChangeValue(forKey:)

Informs the observed object that the value of a given property has changed.

Declaration

func didChangeValue(forKey key: String)

Parameters

key

The name of the property that changed.

Discussion

Use this method when implementing key-value observer compliance manually to inform the observed object that the value at key has just changed. Calls to this method are always paired with a matching call to willChangeValue(forKey:).

Special Considerations

You rarely need to override this method in subclasses, but if you do, be sure to call super.

See Also

Notifying Observers of Changes

func willChangeValue(forKey: String)

Informs the observed object that the value of a given property is about to change.

func willChange(NSKeyValueChange, valuesAt: IndexSet, forKey: String)

Informs the observed object that the specified change is about to be executed at given indexes for a specified ordered to-many relationship.

func didChange(NSKeyValueChange, valuesAt: IndexSet, forKey: String)

Informs the observed object that the specified change has occurred on the indexes for a specified ordered to-many relationship.

func willChangeValue(forKey: String, withSetMutation: NSKeyValueSetMutationKind, using: Set<AnyHashable>)

Informs the observed object that the specified change is about to be made to a specified unordered to-many relationship.

func didChangeValue(forKey: String, withSetMutation: NSKeyValueSetMutationKind, using: Set<AnyHashable>)

Informs the observed object that the specified change was made to a specified unordered to-many relationship.

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