在iOS中切换RTL时，UIAlertController不在中心显示文本

class RTLAlertController: UIAlertController {
    override func viewWillLayoutSubviews() {
        super.viewWillLayoutSubviews()
        
        // 将文本居中显示
        if let messageLabel = self.view.subviews.first?.subviews.first?.subviews.first as? UILabel {
            messageLabel.textAlignment = .center
        }
    }
}

// 使用RTLAlertController替代默认的UIAlertController
let alertController = RTLAlertController(title: "标题", message: "消息", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "确定", style: .default, handler: nil))

// 在切换RTL之前，需要先显示该UIAlertController
self.present(alertController, animated: true, completion: nil)