Question

上午，

我需要帮助。我想要显示我想显示UItextfield错误消息UImenuController错误但这不起作用。我的UItextfield位于UITaBleView单元格中。！

我的班级

@IBOutlet weak var passwordField: UITextField!  


    func textFieldDidEndEditing(textField: UITextField) {

        if textField == passwordField && !Validation.isValidPassword(textField.text){
            displayMenu(textField, errorMessage : "error message")
        }

    }


    func displayMenu(view : UITextField , errorMessage : String){

        let menuItem : UIMenuItem = UIMenuItem(title: errorMessage , action: Selector("showMenu"))
        var menu : UIMenuController = UIMenuController()

        menu.arrowDirection = UIMenuControllerArrowDirection.Up
        menu.menuItems = [menuItem as AnyObject]

        menu.setTargetRect(CGRect(x: 0, y: 0, width: 100, height: 50), inView: self.tableView)
        menu.setMenuVisible(true, animated: true)

        println("display menu")

    }


    func showMenu() {
        println("menu show");
    }



    override func canBecomeFirstResponder() -> Bool {
        return true
    }

    override func canPerformAction(action: Selector, withSender sender: AnyObject?) -> Bool {

        if action == Selector("showMenu") {
            return tableView.canPerformAction(action, withSender: sender)
        }
        return false
    }

错误

2015-02-21 17:54:03.576 Lovia[7870:177566] *** Assertion failure in -[UIMenuController init], /SourceCache/UIKit_Sim/UIKit-3347.6.1/UIMenuController.m:90
2015-02-21 17:54:03.585 Lovia[7870:177566] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'There can only be one UIMenuController instance.'
*** First throw call stack:
(
    0   CoreFoundation                      0x00000001026e4b95 __exceptionPreprocess + 165
    1   libobjc.A.dylib

由于

Answer 1

如果您需要在单元格中显示MenuItem，可以查看：How to show a custom UIMenuItem for a UITableViewCell?

canPerformAction 中的另一个问题：

 override func canPerformAction(action: Selector, withSender sender: AnyObject?) -> Bool {

    if action == Selector("showMenu") {
        return true
    }
    return false
}

UIMenuController在我的tableview中不可见

1 个答案: