Forked from AppsTitude/UICollection and NSFetchedResultsControllerDelegate integration.swift
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UICollectionView and NSFetchedResultsControllerDelegate integration in Swift
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| var fetchedResultsProcessingOperations: [NSBlockOperation] = [] | |
| private func addFetchedResultsProcessingBlock(processingBlock:(Void)->Void) { | |
| fetchedResultsProcessingOperations.append(NSBlockOperation(block: processingBlock)) | |
| } | |
| func controller(controller: NSFetchedResultsController, didChangeObject anObject: AnyObject, atIndexPath indexPath: NSIndexPath?, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath?) { | |
| switch type { | |
| case .Insert: | |
| addFetchedResultsProcessingBlock {self.collectionView!.insertItemsAtIndexPaths([newIndexPath!])} | |
| case .Update: | |
| addFetchedResultsProcessingBlock {self.collectionView!.reloadItemsAtIndexPaths([indexPath!])} | |
| case .Move: | |
| addFetchedResultsProcessingBlock { | |
| // If installsStandardGestureForInteractiveMovement is on | |
| // the UICollectionViewController will handle this on its own. | |
| guard !self.installsStandardGestureForInteractiveMovement else { | |
| return | |
| } | |
| self.collectionView!.moveItemAtIndexPath(indexPath!, toIndexPath: newIndexPath!) | |
| } | |
| case .Delete: | |
| addFetchedResultsProcessingBlock {self.collectionView!.deleteItemsAtIndexPaths([indexPath!])} | |
| } | |
| } | |
| func controller(controller: NSFetchedResultsController, didChangeSection sectionInfo: NSFetchedResultsSectionInfo, atIndex sectionIndex: Int, forChangeType type: NSFetchedResultsChangeType) { | |
| switch type { | |
| case .Insert: | |
| addFetchedResultsProcessingBlock {self.collectionView!.insertSections(NSIndexSet(index: sectionIndex))} | |
| case .Update: | |
| addFetchedResultsProcessingBlock {self.collectionView!.reloadSections(NSIndexSet(index: sectionIndex))} | |
| case .Delete: | |
| addFetchedResultsProcessingBlock {self.collectionView!.deleteSections(NSIndexSet(index: sectionIndex))} | |
| case .Move: | |
| // Not something I'm worrying about right now. | |
| break | |
| } | |
| } | |
| func controllerDidChangeContent(controller: NSFetchedResultsController) { | |
| collectionView!.performBatchUpdates({ () -> Void in | |
| for operation in self.fetchedResultsProcessingOperations { | |
| operation.start() | |
| } | |
| }, completion: { (finished) -> Void in | |
| self.fetchedResultsProcessingOperations.removeAll(keepCapacity: false) | |
| }) | |
| } | |
| deinit { | |
| // Cancel all block operations when VC deallocates | |
| for operation in fetchedResultsProcessingOperations { | |
| operation.cancel() | |
| } | |
| fetchedResultsProcessingOperations.removeAll() | |
| } |
Thank you for this, it's working well.
Thank you for this, it's working well.
https://gist.github.com/AppsTitude/ce072627c61ea3999b8d did most of the hard work :)
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I've been using this successfully but am now trying to use CollectionView.scrollToItem after inserting a new item. Where would you suggest implementing this as I get the 'attempt to scroll to invalid index path' when I put the scrollToItem call immediately after the .insert addFetchjedResultsProcessingBlock call?
Thanks.
Actually I may have solved this. I'll test some more.