每次单击按钮时如何更改标签文本上的int值

Question

//这是我在字符串中也使用颜色标签的代码

var cellIndex: Int = 0
override func viewDidLoad() {
    super.viewDidLoad()
    cellIndex = 1
    let s1 = "word \(cellIndex) to \(cellIndex+7)"
    let mystring:NSString = "\(s1) recovery phrases" as NSString
    var myMutableString = NSMutableAttributedString()
    myMutableString =  NSMutableAttributedString(string:mystring as String, attributes: [NSAttributedString.Key.font:Font.mediumRegularFont()])
    myMutableString.addAttribute(NSAttributedString.Key.foregroundColor, value: Color.darkColor(), range: NSRange(location:0,length:s1.count))
    stepBarView.attributedText = myMutableString
}
@IBAction func onNextButtonTap(_ sender: Any) {
    // i want to change cellIndex Value every time when i press button.
}

Answer 1

你有两个选择

1 用 replacingOccurrences 替换该值，但需要考虑该数字可能有多少位数。 2 再次重新创建整个字符串，这样更快，工作更少

Answer 2

您可以在 cellIndex 中使用 didSet。

var cellIndex: Int = 0 {
    didSet {
        let s1 = "word \(cellIndex) to \(cellIndex+7)"
        let mystring:NSString = "\(s1) recovery phrases" as NSString
        var myMutableString = NSMutableAttributedString()
        myMutableString =  NSMutableAttributedString(string:mystring as String, attributes: [NSAttributedString.Key.font:Font.mediumRegularFont()])
       myMutableString.addAttribute(NSAttributedString.Key.foregroundColor, value: Color.darkColor(), range: NSRange(location:0,length:s1.count))
        stepBarView.attributedText = myMutableString
    }
} 

现在，只要将 value 设置为 cellIndex，它就会使用所需的字符串更新标签。