Question

当我对视图进行平移时，它没有做出反应。以下代码显示了我如何设置手势识别器。我的代码出了什么问题？

class MyViewController : UIViewController {
    override func loadView() {
        self.view.addGestureRecognizer(gestureRecognizerForSetCardFace)
    }

    var gestureRecognizerForSetCardFace: UIPanGestureRecognizer = {
        let recognizer = UIPanGestureRecognizer(target: self, action: #selector(handleSetGesture(gesture:)))
        recognizer.maximumNumberOfTouches = 1
        return recognizer
    }()

     @objc func handleSetGesture(gesture: UIPanGestureRecognizer){
        print("pan")
    }
}

Answer 1

你压倒loadView。如果您实际创建了一个视图并将其分配给self.view，那么这只应该被覆盖。

更改代码以覆盖viewDidLoad。

override func viewDidLoad() {
    super.viewDidLoad()

    self.view.addGestureRecognizer(gestureRecognizerForSetCardFace)
}

Answer 2

您需要添加一些东西 -

为您的动作添加Lazy var。

当属性的初始值为时，延迟属性很有用取决于外部因素，其值直到a之后才知道实例的初始化已完成。

lazy var gestureRecognizerForSetCardFace: UIPanGestureRecognizer = {
        let recognizer = UIPanGestureRecognizer(target: self, action: #selector(handleSetGesture(gesture:)))
        recognizer.maximumNumberOfTouches = 1
        return recognizer
    }()

在viewdidLoad

在控制器的视图加载到内存后调用。

override func viewDidLoad() {
    super.viewDidLoad()
    self.view.addGestureRecognizer(gestureRecognizerForSetCardFace)
}

UIGestureRecognizer没有响应swift 3.0

2 个答案: