有一个按钮减去我按下的下一个按钮的值。 迅速

Question

I have seven buttons labeled 1-7 in my counting app. The counting starts at 0, then when I press a number, it is added onto 0. So if I press 6, the count is at 6. Then I press 3, and the count is now at 9. Now I want to include a subtraction button so that I can go down by hitting the subtract button, then picking the value of my choice. So if I hit the subtraction button followed by the number 2, the count would go back to 7.

    import UIKit

class ViewController: UIViewController {

@IBOutlet weak var Score: UILabel!

var number = 0

@IBAction func oneButton(_ sender: UIButton) {

    var number1 = number + 1
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func twoButton(_ sender: UIButton) {

    var number1 = number + 2
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func threeButton(_ sender: UIButton) {

    var number1 = number + 3
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func fourButton(_ sender: UIButton) {

    var number1 = number + 4
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func fiveButton(_ sender: UIButton) {

    var number1 = number + 5
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func sixButton(_ sender: UIButton) {

    var number1 = number + 6
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func sevenButton(_ sender: UIButton) {

    var number1 = number + 7
    number = number1
    var realNumber = String(number)
    Score.text = realNumber

}


@IBAction func foulButton(_ sender: UIButton) {



}

}

I am not sure what code I should be putting in the foulButton function. Thank you in advance.

Answer 1

I'd start by giving "tags" to each of ur buttons with their numeric value, then you can use a single function for all. Then it will be very easy to simulate a subtraction.

var subtraction = false

@IBAction func buttonAction(_ sender: UIButton) {

    var change = sender.tag
    if subtraction {
       change = change * (-1)
       subtraction = false
    } 

    number = number + change    
    Score.text = String(number)
}

@IBAction func foulButton(_ sender: UIButton) {
    subtraction = !subtraction
}

Answer 2

I think you want to make the button for adding and subtracting values you can make a simple Generic function for this task just like that:-

var count = 0
func addNumber(number:Int) {
    count = count+number
    var realNumber = String(number)
    print(realNumber)
    Score.text = realNumber
}

func subtractNumber(number:Int) {
    count = count-number
    var realNumber = String(number)
    print(realNumber)
    Score.text = realNumber
}


addNumber(number: 4)       //function call from your button
subtractNumber(number: 2)  //by respective values