到代码的iOS UI连接

Question

每次我运行这段给Terminating app due to uncaught exception 'NSUnknownKeyException',setValue:forUndefinedKey:]: this class is not key value coding.'的代码，我所做的就是将button连接到label

class ViewController: UIViewController {

    @IBOutlet weak var lable: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

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

    @IBAction func button(_ sender: Any) {
        lable.text="done"
    }

}

错误将被引用到class AppDelegate: UIResponder, UIApplicationDelegate

Answer 1

转到您的故事板，选择您的ViewController并转到本节

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检查一下这里没有任何无效的出口。如果连接一个出口，然后通过代码更改变量的名称，那么xcode仍然会试图找到前一个接口，并会崩溃。