ios - tableview 编辑模式不允许删除和/或菜单 : what is missing?

Question

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {


    @IBOutlet weak var tableView: UITableView!

    var items = ["foo", "bar", "baz", "mamma mia"]

    override func viewDidLoad() {
        super.viewDidLoad()
         self.tableView.editing = true
         navigationItem.leftBarButtonItem = editButtonItem()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

     func tableView(table1: UITableView,
        numberOfRowsInSection section: Int)
        -> Int {
            return self.items.count
    }

    // `UITableViewCell`s for each section and row
     func tableView(tableView: UITableView,
        cellForRowAtIndexPath indexPath: NSIndexPath)
        -> UITableViewCell {
            let item = self.items[indexPath.row]

            let cell = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as UITableViewCell
            cell.textLabel!.text = item
            return cell
    }

    func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        print ("at editing style")
        if editingStyle == .Delete {

            print ("delete at row: \(indexPath.row)")
        }
        if editingStyle == .Insert {
            print ("insert at row: \(indexPath.row)")

        }
    }

    func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
//       print ("at can edit row: \(indexPath.row)")

        return true
    }


    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath){

    }
}

1. 为什么没有出现菜单/删除按钮？
2. 如果它们(何时)出现，它们是否在 commitEditingStyle 中被处理？

Answer 1

实现这个方法:

func tableView(tableView: UITableView!, editingStyleForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCellEditingStyle {
    return .Delete
}