# observedPresentedItemUbiquityAttributes A list of ubiquity attributes used to generate and send notifications whenever an attribute in the list changes. ``` optional var observedPresentedItemUbiquityAttributes: Set { get } ``` ## Discussion Valid attributes include the [`isUbiquitousItemKey`](/documentation/Foundation/URLResourceKey/isUbiquitousItemKey) attribute and any attribute whose name starts with `ubiquitousItem` or `ubiquitousSharedItem` (or `NSURLUbiquitousItem` or `NSURLUbiquitousSharedItem` in Objective-C). If the property is not implemented, the system generates notifications for all the ubiquity attributes. The system checks this property only when the file coordinator’s [`addFilePresenter(_:)`](/documentation/Foundation/NSFileCoordinator/addFilePresenter(_:)) method is called. Make all changes to this property before calling [`addFilePresenter(_:)`](/documentation/Foundation/NSFileCoordinator/addFilePresenter(_:)). --- 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)