按钮轻按和长按手势

Question

我在手势方面遇到了一些小麻烦。

我正在尝试在同一个按钮上同时使用轻触和长按功能，因此我已经使用了

@IBAction func xxx (sender: UITapGestureRecognizer)

和

@IBAction func xxx (sender: UILongPressGestureRecognizer)

但是当我点击按钮时，它似乎会同时触发两个函数。可能出了什么问题？

func long(longpress: UIGestureRecognizer){
    if(longpress.state == UIGestureRecognizerState.Ended){
    homeScoreBool = !homeScoreBool
    }else if(longpress.state == UIGestureRecognizerState.Began){
        print("began")
    }
}

- Alvin Wan

Answer 1

根据你提供的代码只有两行，很难确定其中哪一部分出现了问题。但是我建议你这样做：创建一个按钮的 outlet。

@IBOutlet weak var myBtn: UIButton!

在您的viewDidLoad()中，将手势添加到按钮上

let tapGesture = UITapGestureRecognizer(target: self, action: "normalTap")  
let longGesture = UILongPressGestureRecognizer(target: self, action: "longTap:")
tapGesture.numberOfTapsRequired = 1
myBtn.addGestureRecognizer(tapGesture)
myBtn.addGestureRecognizer(longGesture)

然后创建处理轻拍的操作

func normalTap(){

    print("Normal tap")
}

func longTap(sender : UIGestureRecognizer){
    print("Long tap")
    if sender.state == .Ended {
    print("UIGestureRecognizerStateEnded")
    //Do Whatever You want on End of Gesture
    }
    else if sender.state == .Began {
        print("UIGestureRecognizerStateBegan.")
        //Do Whatever You want on Began of Gesture
    }
}

Swift 3.0版本：

let tapGesture = UITapGestureRecognizer(target: self, action: #selector(ViewController.normalTap))
let longGesture = UILongPressGestureRecognizer(target: self, action: Selector(("longTap:")))
tapGesture.numberOfTapsRequired = 1
myBtn.addGestureRecognizer(tapGesture)
myBtn.addGestureRecognizer(longGesture)

func normalTap(){

    print("Normal tap")
}

func longTap(sender : UIGestureRecognizer){
    print("Long tap")
    if sender.state == .ended {
        print("UIGestureRecognizerStateEnded")
        //Do Whatever You want on End of Gesture
    }
    else if sender.state == .began {
        print("UIGestureRecognizerStateBegan.")
        //Do Whatever You want on Began of Gesture
    }
}

Swift 5.x的语法已更新：

let tapGesture = UITapGestureRecognizer(target: self, action: #selector(normalTap))
button.addGestureRecognizer(tapGesture)

let longGesture = UILongPressGestureRecognizer(target: self, action: #selector(longTap))
button.addGestureRecognizer(longGesture)

@objc func normalTap(_ sender: UIGestureRecognizer){
    print("Normal tap")
}

@objc func longTap(_ sender: UIGestureRecognizer){
    print("Long tap")
    if sender.state == .ended {
        print("UIGestureRecognizerStateEnded")
        //Do Whatever You want on End of Gesture
    }
    else if sender.state == .began {
        print("UIGestureRecognizerStateBegan.")
        //Do Whatever You want on Began of Gesture
    }
}

- Rashwan L

---

谢谢，它完美地工作了，但是当我尝试长按两次时，它会执行两次操作，您知道为什么吗？谢谢先生。 - Alvin Wan

也许它正在捕捉双击手势？ - Marcelo

@AlvinWan，抱歉回复晚了，这是因为 UILongPressGestureRecognizer 有两种状态，开始和结束。我已更新了代码并提供了示例。请注意，我向longTap添加了一个参数，并在 longGesture 的 UILongPressGestureRecognizer 后加了一个 ":"。 - Rashwan L

如果我有更多的按钮...比如myBtn1、myBtn2和myBtn3呢？ - arakweker

如果我有更多的按钮...比如myBtn1到myBtn10怎么办？有没有办法利用按钮的标签(Tag)呢？ - arakweker

@arakweker，是的，那么您可以使用此标记。您可以通过sender.view?.tag访问标记。还要注意每个按钮必须有自己的手势声明，但您仍然可以调用相同的函数。例如：let tapForFirstButton = UITapGestureRecognizer(target: self, action: #selector(normalTap(_:)))和let tapForSecondButton = UITapGestureRecognizer(target: self, action: #selector(normalTap(_:)))。 - Rashwan L