更改 Swift/ SwiftUI 中十进制数字的字体大小

Question

所以我需要使小数位小于实际数字，我将在下面向您展示我的意思。

这是我的代码：

import SwiftUI

struct BalanceDetailsView: View {
    //MARK: - PROPERTIES
    var balance: Float
    var balanceString: String {
        return balance.formattedWithSeparator
    }
    //MARK: - BODY
    var body: some View {
        VStack{
            HStack{
                    Text(balanceString)
                        .font(.custom(K.fonts.gilroyBold, size: 24))
                        .multilineTextAlignment(.center)
                        .padding(.top)
             
            }//:VSTACK
        }//:HSTACK
    }
}

struct BalanceDetailsView_Previews: PreviewProvider {
    static var previews: some View {
        BalanceDetailsView(balance: 43678)
            .previewLayout(.sizeThatFits)
    }
}



//Formatter extension i used to get this code
extension Formatter {
    static let withSeparator: NumberFormatter = {
        let formatter = NumberFormatter()
        formatter.numberStyle = .decimal

        // minimum decimal digit, eg: to display 2 as 2.00
        formatter.minimumFractionDigits = 2

        // maximum decimal digit, eg: to display 2.5021 as 2.50
        formatter.maximumFractionDigits = 2
        
        return formatter
    }()
}

extension Numeric {
    var formattedWithSeparator: String { Formatter.withSeparator.string(for: self) ?? "" }
}

我得到的结果	我需要的结果

Answer 1

当您知道字符串的确切格式时，例如在本例中最小字符串长度为 4("0.00") ，您可以安全地使用dropLast和dropFirst。

我建议转向2常量priceFractionDigits以减少代码中常量的使用。

然后您可以使用字符串连接，它将Text按基线对齐。

struct BalanceText: View {
    var balance: Float
    var balanceString: String {
        return balance.formattedWithSeparator
    }
    
    var body: some View {
        Text(balanceString.dropLast(priceFractionDigits))
            .font(.system(size: 24))
            +
            Text(balanceString.dropFirst(balanceString.count - priceFractionDigits))
            .font(.system(size: 18))
    }
}

private let priceFractionDigits = 2

extension Formatter {
    static let withSeparator: NumberFormatter = {
        let formatter = NumberFormatter()
        formatter.numberStyle = .decimal

        // minimum decimal digit, eg: to display 2 as 2.00
        formatter.minimumFractionDigits = priceFractionDigits

        // maximum decimal digit, eg: to display 2.5021 as 2.50
        formatter.maximumFractionDigits = priceFractionDigits
        
        return formatter
    }()
}

用法

BalanceText(balance: balance)