Question

所以我正在开发一个选择器，它提醒用户平移对象而不是点击它。以下代码是动画：

func labelTapped(sender:UITapGestureRecognizer)->Void{
    UIView.animateWithDuration(0.2, delay: 0, options: UIViewAnimationOptions.CurveEaseIn, animations: {
        sender.view.frame = CGRectMake(sender.view.frame.origin.x + 15, sender.view.frame.origin.y, sender.view.frame.width, sender.view.frame.height)
        }, completion:
        {(value:Bool) in
            UIView.animateWithDuration(0.2, delay: 0, options: UIViewAnimationOptions.CurveEaseOut, animations: {
                sender.view.frame = CGRectMake(sender.view.frame.origin.x - 15, sender.view.frame.origin.y, sender.view.frame.width, sender.view.frame.height)
                }, completion:
                {(value:Bool) in
                })
        })
}

现在回到对象本身。我正在分配UITapGestureRecognizer并将其添加到对象中，但我不确定它是如何工作的，因为回到Objective-C，我们曾经这样做：

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(labelTapped)];

其中不需要参数。但是在Swift中，我必须在labelTapped之后在括号中输入一个参数，因为它会给我一个Missing argument for parameter #1 in call错误：

let labelTap1=UITapGestureRecognizer(target: self, action: labelTapped())

我该如何解决这个问题？谢谢！

Answer 1

动作选择器是一个以冒号结尾的字符串，它告诉它有一个参数（发送者）：

let labelTap1=UITapGestureRecognizer(target: self, action: "labelTapped:")

Answer 2

  override func viewDidAppear(animated: Bool) {
        super.viewDidAppear(animated)

        let tapRecognizer = UITapGestureRecognizer(target: self, action: "handleSingleTap:")
        tapRecognizer.numberOfTapsRequired = 1
        self.view.addGestureRecognizer(tapRecognizer)

    }

 func handleSingleTap(recognizer: UITapGestureRecognizer) {

        self.view.endEditing(true)

    }

在Swift中获取UITapGestureRecognizer的发件人

2 个答案: