【发布时间】：2015-10-01 17:46:24
【问题描述】：
这是一个错误：
CoreData：错误：严重的应用程序错误。在调用 -controllerDidChangeContent: 期间，从 NSFetchedResultsController 的委托中捕获了一个异常。尝试使用 userInfo (null) 删除并重新加载相同的索引路径 ({length = 2, path = 0 - 0})
这是我典型的NSFetchedResultsControllerDelegate：
func controllerWillChangeContent(controller: NSFetchedResultsController) {
tableView.beginUpdates()
}
func controller(controller: NSFetchedResultsController, didChangeSection sectionInfo: NSFetchedResultsSectionInfo, atIndex sectionIndex: Int, forChangeType type: NSFetchedResultsChangeType) {
let indexSet = NSIndexSet(index: sectionIndex)
switch type {
case .Insert:
tableView.insertSections(indexSet, withRowAnimation: .Fade)
case .Delete:
tableView.deleteSections(indexSet, withRowAnimation: .Fade)
case .Update:
fallthrough
case .Move:
tableView.reloadSections(indexSet, withRowAnimation: .Fade)
}
}
func controller(controller: NSFetchedResultsController, didChangeObject anObject: NSManagedObject, atIndexPath indexPath: NSIndexPath?, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath?) {
switch type {
case .Insert:
if let newIndexPath = newIndexPath {
tableView.insertRowsAtIndexPaths([newIndexPath], withRowAnimation: .Fade)
}
case .Delete:
if let indexPath = indexPath {
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
}
case .Update:
if let indexPath = indexPath {
tableView.reloadRowsAtIndexPaths([indexPath], withRowAnimation: .None)
}
case .Move:
if let indexPath = indexPath {
if let newIndexPath = newIndexPath {
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
tableView.insertRowsAtIndexPaths([newIndexPath], withRowAnimation: .Fade)
}
}
}
}
func controllerDidChangeContent(controller: NSFetchedResultsController) {
tableView.endUpdates()
}
在viewDidLoad():
private func setupOnceFetchedResultsController() {
if fetchedResultsController == nil {
let context = NSManagedObjectContext.MR_defaultContext()
let fetchReguest = NSFetchRequest(entityName: "DBOrder")
let dateDescriptor = NSSortDescriptor(key: "date", ascending: false)
fetchReguest.predicate = NSPredicate(format: "user.identifier = %@", DBAppSettings.currentUser!.identifier )
fetchReguest.sortDescriptors = [dateDescriptor]
fetchReguest.fetchLimit = 10
fetchedResultsController = NSFetchedResultsController(fetchRequest: fetchReguest, managedObjectContext: context, sectionNameKeyPath: "identifier", cacheName: nil)
fetchedResultsController.delegate = self
try! fetchedResultsController.performFetch()
}
}
【问题讨论】：
标签： ios swift ios9 nsfetchedresultscontroller