# handleError(_:userInteractionPermitted:) Handles an error that occurs during an attempt to read, save, or revert a document. ``` func handleError(_ error: any Error, userInteractionPermitted: Bool) ``` ## Parameters `error` An object encapsulating information about an error encountered in an attempt to open, save, or revert a document. The error domain is . The error code is one of the `enum` constants declared in `FoundationErrors.h`. `userInteractionPermitted` If , no attempt is (or should be) made to present a modal view to the user. This value can be in cases such as when a save operation fails while the application is being suspended. If this parameter is , UIKit or your override may present error information to the user in a modal view and (optionally) allow the user to resolve the error. ## Discussion Typical [`UIDocument`](/documentation/UIKit/UIDocument) subclasses don’t need to call or override this method. Instead, they can observe the [`stateChangedNotification`](/documentation/UIKit/UIDocument/stateChangedNotification) notification to be notified of changes in document state. In their notification handler, they can check the value of the [`documentState`](/documentation/UIKit/UIDocument/documentState) property and proceed accordingly. See [`Resolve conflicts and handle errors`](/documentation/UIKit/UIDocument#Resolve-conflicts-and-handle-errors) for a discussion of this. If you’re using managed documents (instances of the [`UIManagedDocument`](/documentation/UIKit/UIManagedDocument) subclass), you must subclass this method and, if desired, the [`finishedHandlingError(_:recovered:)`](/documentation/UIKit/UIDocument/finishedHandlingError(_:recovered:)) method. Subclassing allows your app to observe errors in saving or validation. The [`stateChangedNotification`](/documentation/UIKit/UIDocument/stateChangedNotification) notification doesn’t contain a `userInfo` dictionary and so doesn’t convey specific error information. If you directly call any of the advanced reading and writing methods that have an error-object parameter (for example, [`writeContents(_:andAttributes:safelyTo:for:)`](/documentation/UIKit/UIDocument/writeContents(_:andAttributes:safelyTo:for:))) and that call returns an object by indirection, you should call this method ([`handleError(_:userInteractionPermitted:)`](/documentation/UIKit/UIDocument/handleError(_:userInteractionPermitted:))), passing in the error object. This method is called by the default implementations of [`open(completionHandler:)`](/documentation/UIKit/UIDocument/open(completionHandler:)) and [`save(to:for:completionHandler:)`](/documentation/UIKit/UIDocument/save(to:for:completionHandler:)) when [`UIDocument`](/documentation/UIKit/UIDocument) encounters a reading or writing error, respectively. If you override this method and don’t invoke the superclass implementation (`super`), you’re responsible for the following: - Calling [`finishedHandlingError(_:recovered:)`](/documentation/UIKit/UIDocument/finishedHandlingError(_:recovered:)) when you’re finished handling the error — for example, when the application doesn’t require any additional user feedback about the error. - Implementing [`userInteractionNoLongerPermitted(forError:)`](/documentation/UIKit/UIDocument/userInteractionNoLongerPermitted(forError:)) to conclude error handling immediately. If `userInteractionPermitted` is , you should immediately handle the error and call [`finishedHandlingError(_:recovered:)`](/documentation/UIKit/UIDocument/finishedHandlingError(_:recovered:)) within the context of the [`handleError(_:userInteractionPermitted:)`](/documentation/UIKit/UIDocument/handleError(_:userInteractionPermitted:)). --- 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)