请看下面的示例代码:
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let letterButton = UIButton.buttonWithType(.Custom) as UIButton
self.view.addSubview(letterButton)
letterButton.addTarget(self, action:Selector("buttonDidTap:"), forControlEvents: .TouchUpInside)
}
func buttonDidTap(button: UIButton!) {
print(button.char)
}
}
只要 Select 器是public或internal，UIButton的目标操作就可以正常工作，但如果是private，则会因unrecognized selector sent to instance而崩溃
我有没有办法做到这一点？我不想让tap函数公开或内部.