相关疑难解决方法(0)

我使用的是NSTableView + CoreData + NSFetchedResultsController的相当标准的设置，相关的视图控制器为NSFetchedResultsControllerDelegate来接收更改。这是来自视图控制器的相关代码位：

func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?){

    print("Change type \(type) for indexPath \(String(describing: indexPath)), newIndexPath \(String(describing: newIndexPath)). Changed object: \(anObject). FRC by this moment has \(String(describing: self.frc?.fetchedObjects?.count)) objects, tableView has \(self.tableView.numberOfRows) rows")

    switch type {
    case .insert:
        if let newIndexPath = newIndexPath {
            tableView.insertRows(at: [newIndexPath.item], withAnimation: .effectFade)
        }
    case .delete:
        if let indexPath = indexPath {
            tableView.removeRows(at: [indexPath.item], withAnimation: .effectFade)
        }
    case .update:
        if let indexPath = …