ios - UILongPressGestureRecognizer 未运行功能

Question

在我的 viewdidload() 中，我像这样初始化了 longpressgesturerecognizer

override func viewDidLoad() {
    super.viewDidLoad()
    let lpgr = UILongPressGestureRecognizer(target: self, action: "action:")

    lpgr.minimumPressDuration = 2.0

    Capture.addGestureRecognizer(lpgr)

    // Do any additional setup after loading the view.
}

然后我尝试运行这个功能，它后来成为相机的录制按钮

func action(gestureRecognizer:UIGestureRecognizer) {
    print("pressed")

}
@IBOutlet weak var Capture: UIProgressView!