尤里卡：避免在小数点行上使用多个小数点

Question

我正在尝试通过Eureka表单实现计算器。

在小数行中，它允许输入多个小数点。我想将其限制为仅一个小数点。例如，我可以输入“ 3 .... 5”。但是我只想输入“ 3.5”。

这是我的代码：

<<< DecimalRow() {
                $0.tag = Tags.term
                $0.title = "Term (Years)"
                $0.baseCell.accessibilityLabel = $0.title
                $0.formatter = DecimalFormatter()
                $0.placeholder = "Years"
                $0.add(rule: RuleRequired(msg: "Term field is required."))
                $0.add(rule: RuleGreaterThan(min: 0, msg: "Term must be 
                greater than zero."))
                $0.useFormatterDuringInput = true
                $0.validationOptions = .validatesOnDemand

// DecimalFormatter 

class DecimalPercentageFormatter: NumberFormatter {
    init(minimumFractionDigits: Int = 2, maximumFractionDigits: Int = 2) {
        super.init()
        self.minimumFractionDigits = minimumFractionDigits
        self.maximumFractionDigits = maximumFractionDigits
        locale = Locale.current
        numberStyle = .percent
        positiveSuffix = "%"
        negativeSuffix = "%"
    }
}