致命错误：从 Core Data/NSFetchedResultsController 删除对象时 UnsafeRawBufferPointer 的计数为负数

Question

这是我第一次使用 AppKit 和

NSTableView

。它由核心数据

NSFetchedResultsController

支持。当数据集发生更改时，会发送

Notification

：

func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?) {
    guard let links = self.fetchedResultsController.fetchedObjects else {
        return
    }

    if self.viewContext.hasChanges {
        try? self.viewContext.save()
    }
        
    self._links = links
    NotificationCenter.default.post(name: .reloadLinkList, object: nil)
}

NotificationCenter.default.publisher(for: .reloadLinkList).receive(on: RunLoop.main).sink { notification in
    self.list.tableView.reloadData()
    self.list.linksModel.selectedRows = IndexSet([])
}
.store(in: &cancellables)

这对于插入和更新数据非常有用。当我尝试删除某些内容时，我得到：

Thread 1: Fatal error: UnsafeRawBufferPointer with negative count

删除选定对象的代码如下：

// selector methode for UIMenuItem`s action
@objc func onDeleteSelectedLinks(_ sender: AnyObject) {
    list.linksModel.deleteLinks(links: selectedLinks)
}

// Method for deleting links from the view context
func deleteLinks(links: [LBLink]) {
    for link in links {
        self.viewContext.delete(link)
    }
}

感谢您提前提供的任何帮助！

Answer 1

我是如何解决这个问题的

Answer 2

就我而言，我只是忘记在文件顶部导入 CoreData 框架。

import CoreData