ios - 如何从 UITableViewController 中删除行

Question

我有 UITableViewController。它具有来自文档目录中文件数组的数据。我想用这个方法删除行 self.navigationItem.leftBarButtonItem = self.editButtonItem()
但我做到了，文件被删除但行没有消失。我尝试了几种方法，但它们没有帮助我。我用 CoreData 的数据做了很多次。但我不知道如何做到这一点。请帮助我。

    override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if editingStyle == .Delete {
            tableView.beginUpdates()
            let currentSong = listOfMP3Files[indexPath.row]
            println(currentSong)
            let directory = fileManager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains: NSSearchPathDomainMask.UserDomainMask).first as! NSURL
            let url = directory.URLByAppendingPathComponent(currentSong)
//            println(url)
//            println(indexPath)
            fileManager.removeItemAtURL(url, error: nil)
            tableView.beginUpdates()
            tableView.deleteRowsAtIndexPaths(NSArray(object: indexPath) as [AnyObject], withRowAnimation: UITableViewRowAnimation.Automatic)
            tableView.endUpdates()
        } else if editingStyle == .Insert {

        }
    }

    func controller(controller: NSFetchedResultsController, didChangeObject anObject: AnyObject, atIndexPath indexPath: NSIndexPath?, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath?) {
        switch type {
        case NSFetchedResultsChangeType.Insert:
            tableView.insertRowsAtIndexPaths([newIndexPath!], withRowAnimation: UITableViewRowAnimation.Fade)
            break
        case NSFetchedResultsChangeType.Delete:
            tableView.deleteRowsAtIndexPaths([indexPath!], withRowAnimation: UITableViewRowAnimation.Fade)
            break
        case NSFetchedResultsChangeType.Move:
            tableView.deleteRowsAtIndexPaths([indexPath!], withRowAnimation: UITableViewRowAnimation.Fade)
            tableView.insertRowsAtIndexPaths([newIndexPath!], withRowAnimation: UITableViewRowAnimation.Fade)
            break
        case NSFetchedResultsChangeType.Update:
            tableView.cellForRowAtIndexPath(indexPath!)
        default: break
        }
    }

    func controller(controller: NSFetchedResultsController, didChangeSection sectionInfo: NSFetchedResultsSectionInfo, atIndex sectionIndex: Int, forChangeType type: NSFetchedResultsChangeType) {
        switch type {
        case NSFetchedResultsChangeType.Insert:
            tableView.insertSections(NSIndexSet(index: sectionIndex), withRowAnimation: UITableViewRowAnimation.Fade)
        case NSFetchedResultsChangeType.Delete:
            tableView.deleteSections(NSIndexSet(index: sectionIndex), withRowAnimation: UITableViewRowAnimation.Fade)
        case NSFetchedResultsChangeType.Move:
            tableView.deleteSections(NSIndexSet(index: sectionIndex), withRowAnimation: UITableViewRowAnimation.Fade)
            tableView.insertSections(NSIndexSet(index: sectionIndex), withRowAnimation: UITableViewRowAnimation.Fade)
        case NSFetchedResultsChangeType.Update:
            break
        default: break
        }
    }

    func controllerDidChangeContent(controller: NSFetchedResultsController) {
        tableView.endUpdates()
    }

    func controllerWillChangeContent(controller: NSFetchedResultsController) {
        tableView.beginUpdates()
    }

第二种变体

    override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if editingStyle == .Delete {
            tableView.beginUpdates()
            let currentSong = listOfMP3Files[indexPath.row]
            println(currentSong)
            let directory = fileManager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains: NSSearchPathDomainMask.UserDomainMask).first as! NSURL
            let url = directory.URLByAppendingPathComponent(currentSong)
//            println(url)
//            println(indexPath)
            fileManager.removeItemAtURL(url, error: nil)
            tableView.beginUpdates()
            tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Automatic)
            tableView.endUpdates()
        } else if editingStyle == .Insert {

        }
    }

Answer 1

您缺少调用 removeAtIndex() 的行，它从数据源数组中删除指定索引处的项目

tableView.beginUpdates()
listOfMP3Files.removeAtIndex(indexPath.row) //Add this line 
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Automatic)
tableView.endUpdates()