ios - Swift:函数中的 UIAlert - 使用未解析的标识符 'present'

Question

我试图限制代码的显示，所以我只想调用包含两个字符串的函数来使用 1 行而不是 5 行更快地创建 uialert/

我得到的错误

Use of unresolved identifier 'present'

在线

present(alert, animated: true, completion: nil)

// Controlling Alerts for Errors
func showAlert(titleString: String, messageString: String) {

 // Alert to go to Settings
 let alert = UIAlertController(title: titleString, message: messageString, preferredStyle: .alert)

 alert.addAction(UIAlertAction(title: "Dismiss", style: .default, handler: { _ in
     alert.dismiss(animated: true, completion: nil)
 }))

 self.present(alert, animated: true, completion: nil)
}

Answer 1

在评论中，您解释说这是一个独立的功能。如果您将它作为 UIViewController 的扩展，它应该可以工作，例如:

extension UIViewController {
    public func showAlert(_ title:String, _ message:String) {
        let alertVC = UIAlertController(
            title: title,
            message: message,
            preferredStyle: .alert)
        let okAction = UIAlertAction(
            title: "OK",
            style: .cancel,
            handler: { action -> Void in
        })
        alertVC.addAction(okAction)
        present(
            alertVC,
            animated: true,
            completion: nil)
    }

并在 UIViewController 中调用它:

showAlert(
    "Could Not Send Email", 
    "Your device could not send e-mail.  Please check e-mail configuration and try again."
)