在iOS 12中更改UITabBarItem徽章字体

import UIKit

class CustomTabBarItem: UITabBarItem {
    override var badgeValue: String? {
        didSet {
            setBadgeValue(badgeValue)
        }
    }
    
    private func setBadgeValue(_ value: String?) {
        if let value = value {
            let font = UIFont.systemFont(ofSize: 12) // 自定义字体
            let textColor = UIColor.white // 自定义字体颜色
            
            let attributes: [NSAttributedString.Key: Any] = [
                .font: font,
                .foregroundColor: textColor
            ]
            
            let attributedString = NSAttributedString(string: value, attributes: attributes)
            badgeTextAttributes = [NSAttributedString.Key.foregroundColor.rawValue: textColor]
            badgeValue = attributedString.string
        } else {
            badgeValue = nil
        }
    }
}

let customTabBarItem = CustomTabBarItem()
customTabBarItem.badgeValue = "3"