将 Button 标签名称取为 UILongPressGestureRecognizer，将 var 和 return 值更改为 Button 的标签

Question

请帮帮我。我想做什么：我有一些变量和按钮。当我长按按钮时，我想要带有文本字段的警报弹出窗口。然后我想输入一些值 (Int)，然后将按钮的标签更改为 (textField value + previous)。我想为多个按钮编写一个函数。我尝试做的事情：

func addLongPressGesture(by sender: UIButton){
    let longPress = UILongPressGestureRecognizer(target: self, action: #selector(longPress(gesture:)))
    longPress.minimumPressDuration = 1
    sender.addGestureRecognizer(longPress)
}

@objc func longPress(gesture: UILongPressGestureRecognizer) {
    if gesture.state == UIGestureRecognizer.State.began {
        print("Long Press")

        var textField = UITextField()
        let alert = UIAlertController(title: "How much?", message: "", preferredStyle: .alert)
        let action = UIAlertAction(title: "Add", style: .default) { (action) in

            if let howMuch = textField.text {
                self.VARIABLE1 = self.VARIABBLE1 + Int(howMuch)!
                self.viewWillAppear(true)
            }
        }
        alert.addAction(action)
        alert.addTextField { (alertTextField) in
            textField = alertTextField
            textField.placeholder = "How much?"
        }
           present(alert, animated: true, completion: nil)
    }
}

我希望 VARIABLE1 根据我长按的按钮进行更改

Answer 1

听起来您声明了多个变量，每个按钮一个。这是您应该开始使用数组的好兆头。声明一个数组而不是多个变量：

var totals = Array(repeating: 0, count: <however many buttons you have>)

然后，给每个按钮一个不同的 tag。您也可以在情节提要中设置它。第一个按钮的标签为 0，第二个按钮的标签为 1，依此类推。

在longPress中获取用gesture.view点击的按钮，获取标签。标签是您应该递增的数组的索引：

if let howMuch = textField.text {
    self.totals[gesture.view!.tag] += Int(howMuch)! // Note: you should probably unwrap the Int? safely
    self.viewWillAppear(true) // Note: you shouldn't really call this yourself
}

将 Button 标签名称取为 UILongPressGestureRecognizer，将 var 和 return 值更改为 Button 的标签

Take Button label name to UILongPressGestureRecognizer, change var and return value to Button's label

alert

long-press

swift