<!--
{
  "documentType" : "article",
  "framework" : "AppKit",
  "identifier" : "/documentation/AppKit/nib-loading-keys",
  "metadataVersion" : "0.1.0",
  "role" : "collectionGroup",
  "title" : "Nib Loading Keys"
}
-->

# Nib Loading Keys

The `NSNib` class uses the following constants which are used as keys in the dictionary passed to [`instantiateNibWithExternalNameTable:`](/documentation/AppKit/NSNib/instantiateNibWithExternalNameTable:).

## Topics

### Constants

[`extern NSString * NSNibOwner;`](/documentation/AppKit/NSNibOwner)

The external object that is responsible for the instantiated nib.

[`extern NSString * NSNibTopLevelObjects;`](/documentation/AppKit/NSNibTopLevelObjects)

An `NSMutableArray` object that, if present, is populated with the top-level objects of the newly instantiated nib.


---

Copyright &copy; 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)