# classes(forCustomParameterID:) Returns the classes of the objects contained in the custom parameter with the given ID. ``` optional func classes(forCustomParameterID parameterID: UInt32) -> Set ``` ## Parameters `parameterID` The parameter ID of the classes to be determined. ## Return Value An NSSet of classes of the specified parameter ID. ## Discussion When you make custom parameters, the host needs to know the classes of the parameters to store and unarchive them from disk. This method returns the Objective-C set of classes that the parameters are members of. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)