TouchUpInside 上的 Swift addTarget 错误

Question

我在 View 上添加了一个按钮，并使用 addTarget 绑定(bind)事件来调用 self.testp，但是当我运行它时，发生了一个错误:

2015-06-19 23:08:29.237 UI[16978:1700826] -[UI.ViewController testp:]: unrecognized selector sent to instance 0x7864d4a0
2015-06-19 23:08:29.240 UI[16978:1700826] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UI.ViewController testp:]: unrecognized selector sent to instance 0x7864d4a0'

代码是:

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()
    var btn:UIButton = UIButton.buttonWithType(UIButtonType.DetailDisclosure) as! UIButton
    btn.frame = CGRectMake(10, 150, 100, 30)
    btn.setTitle("button", forState: UIControlState.Normal)

    //!!!!!!DID NOT WORK
    btn.addTarget(self, action: Selector("testp:"), forControlEvents: UIControlEvents.TouchUpInside);

    self.view.addSubview(btn)

    func testp(){
        println("tttt")
    }
}
}

为什么？!!

Answer 1

只需从您的选择器中删除 :，您的代码将是:

btn.addTarget(self, action: Selector("testp"), forControlEvents: UIControlEvents.TouchUpInside)

并将您的函数放在 viewDidLoad 方法之外，但放在 ViewController 类中。

如果您的函数有如下所示的参数，您可以使用 "testp:":

func testp(yourArgument: String){
    println("tttt")
}