我不断收到此错误'UIAlertView'在iOS 9.0中已被弃用“

Question

继续收到此错误：

'UIAlertView'在iOS 9.0中已被弃用：UIAlertView已弃用。使用UIAlertController而不是UIAlertControllerStyleAlert的preferredStyle

有人可以帮我编辑这段代码吗？

    if #available(iOS 8.0, *) {
        let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: UIAlertControllerStyle.alert)


        alert.addAction(UIAlertAction(title: alertOKTitle, style:.destructive, handler: { alertAction in
            self.okButtonPressed()
            alert.dismiss(animated: true, completion: nil)
        }))

        alert.addAction(UIAlertAction(title: alertCancelTitle, style:.cancel, handler:{ alertAction in
            self.cancelButtonPressed()
            alert.dismiss(animated: true, completion: nil)
        }))

        alert.addAction(UIAlertAction(title: alertRemindLaterTitle, style:.default, handler: { alertAction in
            self.remindLaterButtonPressed()
            alert.dismiss(animated: true, completion: nil)
        }))

        let appDelegate = UIApplication.shared.delegate as! AppDelegate
        let controller = appDelegate.window?.rootViewController

        controller?.present(alert, animated: true, completion: nil)
    } else {
        let alert = UIAlertView()
        alert.title = alertTitle
        alert.message = alertMessage
        alert.addButton(withTitle: alertCancelTitle)
        alert.addButton(withTitle: alertRemindLaterTitle)
        alert.addButton(withTitle: alertOKTitle)
        alert.delegate = self
        alert.show()
    }


}

internal func alertView(_ alertView: UIAlertView , clickedButtonAt buttonIndex: Int){

    if(buttonIndex == 0)
    {
        cancelButtonPressed()
    }
    else if(buttonIndex == 1)
    {
        remindLaterButtonPressed()
    }
    else if(buttonIndex == 2)
    {
        okButtonPressed()
    }

    alertView.dismiss(withClickedButtonIndex: buttonIndex, animated: true)

}

Answer 1

正如错误所述，UIAlertView从iOS 9.0开始被弃用。 UIAlertController已添加到iOS 8.0中。您的代码正确选择在iOS 8.0或更高版本下使用UIAlertController。

问题是您的代码尝试使用UIAlertView进行早于iOS 8.0的任何操作。但是，您的应用程序的部署目标未针对iOS 7或更早版本设置。因此，编译器告诉您UIAlertView已被弃用。

由于您实际上不会支持iOS 8.0之前的任何内容，因此不需要if #available(iOS 8.0, *)或UIAlertView。只需使用UIAlertController编写代码，不要担心UIAlertView。

您发布的所有代码都可以简化为UIAlertController部分：

let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: UIAlertControllerStyle.alert)

alert.addAction(UIAlertAction(title: alertOKTitle, style:.destructive, handler: { alertAction in
    self.okButtonPressed()
    alert.dismiss(animated: true, completion: nil)
}))

alert.addAction(UIAlertAction(title: alertCancelTitle, style:.cancel, handler:{ alertAction in
    self.cancelButtonPressed()
    alert.dismiss(animated: true, completion: nil)
}))

alert.addAction(UIAlertAction(title: alertRemindLaterTitle, style:.default, handler: { alertAction in
    self.remindLaterButtonPressed()
    alert.dismiss(animated: true, completion: nil)
}))

let appDelegate = UIApplication.shared.delegate as! AppDelegate
let controller = appDelegate.window?.rootViewController

controller?.present(alert, animated: true, completion: nil)