@IBAction func Alert(sender: UIButton) {

    var alertView:UIAlertView = UIAlertView()
    alertView.title = "Alert!"
    alertView.message = "Message"
    alertView.delegate = self
    alertView.addButtonWithTitle("OK")

    alertView.show()

}

试试这个

点击查看

@IBAction func testClick(sender: UIButton) {

  var uiAlert = UIAlertController(title: "Title", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
  self.presentViewController(uiAlert, animated: true, completion: nil)

  uiAlert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: { action in
   println("Click of default button")
  }))

  uiAlert.addAction(UIAlertAction(title: "Cancel", style: .Cancel, handler: { action in
   println("Click of cancel button")
  }))

}

完成两个按钮确定&取消

我还有一招。假设您有5个类，其中要应用注销警报。尝试使用swift类扩展。

文件-新建- Swift类-命名。

增加如下内容:

public extension UIViewController
{

    func makeLogOutAlert()
    {
        var refreshAlert = UIAlertController(title: "Log Out", message: "Are You Sure to Log Out ? ", preferredStyle: UIAlertControllerStyle.Alert)

        refreshAlert.addAction(UIAlertAction(title: "Confirm", style: .Default, handler: { (action: UIAlertAction!) in
            self.navigationController?.popToRootViewControllerAnimated(true)
        }))

        refreshAlert.addAction(UIAlertAction(title: "Cancel", style: .Default, handler: { (action: UIAlertAction!) in
            refreshAlert .dismissViewControllerAnimated(true, completion: nil)
        }))

        presentViewController(refreshAlert, animated: true, completion: nil)
    }
}

实现使用:self.makeLogOutAlert()。希望能有所帮助。

试试这个。 把波纹代码在按钮。

let alert = UIAlertController(title: "Your_Title_Text", message: "Your_MSG", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Your_Text", style: UIAlertActionStyle.default, handler: nil))
self.present(alert, animated:true, completion: nil)

下面是警报视图和动作表的可重用代码，只需写一行在应用程序的任何地方显示警报

class AlertView{

    static func show(title:String? = nil,message:String?,preferredStyle: UIAlertControllerStyle = .alert,buttons:[String] = ["Ok"],completionHandler:@escaping (String)->Void){
        let alert = UIAlertController(title: title, message: message, preferredStyle: preferredStyle)

        for button in buttons{

            var style = UIAlertActionStyle.default
            let buttonText = button.lowercased().replacingOccurrences(of: " ", with: "")
            if buttonText == "cancel"{
                style = .cancel
            }
            let action = UIAlertAction(title: button, style: style) { (_) in
                completionHandler(button)
            }
            alert.addAction(action)
        }

        DispatchQueue.main.async {
            if let app = UIApplication.shared.delegate as? AppDelegate, let rootViewController = app.window?.rootViewController {
                rootViewController.present(alert, animated: true, completion: nil)
            }

        }
    }
}

用法:

class ViewController: UIViewController {

    override func viewWillAppear(_ animated: Bool) {
        AlertView.show(title: "Alert", message: "Are you sure ?", preferredStyle: .alert, buttons: ["Yes","No"]) { (button) in
            print(button)
        }
    }

}

通过Swift 2的协议扩展，你可以创建一个为视图控制器提供默认实现的协议:

ShowsAlert.swift

import UIKit

protocol ShowsAlert {}

extension ShowsAlert where Self: UIViewController {
    func showAlert(title: String = "Error", message: String) {
        let alertController = UIAlertController(title: title, message: message, preferredStyle: .Alert)
        alertController.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
        presentViewController(alertController, animated: true, completion: nil)
    }
}

ViewController.swift

class ViewController: UIViewController, ShowsAlert {
    override func viewDidLoad() {
        super.viewDidLoad()
        showAlert(message: "Hey there, I am an error message!")
    }
}