controllerWillChangeContent(_:)
Notifies the receiver that the fetched results controller is about to start processing of one or more changes due to an add, remove, move, or update.
Declaration
optional func controllerWillChangeContent(_ controller: NSFetchedResultsController<any NSFetchRequestResult>)Parameters
- controller:
The fetched results controller that sent the message.
Discussion
This method is invoked before all invocations of controller(_:didChange:at:for:newIndexPath:) and controller(_:didChange:atSectionIndex:for:) have been sent for a given change event (such as the controller receiving a NSManagedObjectContextDidSave notification).
See Also
Related Documentation
- Core Data Programming Guide