我已经做了一个单例类，以便从应用程序的任何地方使用:https://github.com/Swinny1989/Swift-Popups

然后你可以创建一个带有多个按钮的弹出窗口，如下所示:

Popups.SharedInstance.ShowAlert(self, title: "Title goes here", message: "Messages goes here", buttons: ["button one" , "button two"]) { (buttonPressed) -> Void in
    if buttonPressed == "button one" { 
      //Code here
    } else if buttonPressed == "button two" {
        // Code here
    }
}

或者弹出一个按钮，像这样:

Popups.SharedInstance.ShowPopup("Title goes here", message: "Message goes here.")

它不工作的原因是因为你传递给函数的某个值不正确。swift不像Objective-C，你可以把nil放在类类型的参数中，没有任何限制(可能是)。参数otherButtonTitles被定义为非可选的，其类型的末尾没有(?)。所以你必须传递一个具体的值给它。

你可以使用标准的构造函数创建一个UIAlert，但是“遗留的”构造函数似乎不起作用:

let alert = UIAlertView()
alert.title = "Alert"
alert.message = "Here's a message"
alert.addButtonWithTitle("Understood")
alert.show()

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

一个按钮

class ViewController: UIViewController {

    @IBAction func showAlertButtonTapped(_ sender: UIButton) {

        // create the alert
        let alert = UIAlertController(title: "My Title", message: "This is my message.", preferredStyle: UIAlertController.Style.alert)

        // add an action (button)
        alert.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil))

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

两个按钮

class ViewController: UIViewController {

    @IBAction func showAlertButtonTapped(_ sender: UIButton) {

        // create the alert
        let alert = UIAlertController(title: "UIAlertController", message: "Would you like to continue learning how to use iOS alerts?", preferredStyle: UIAlertController.Style.alert)

        // add the actions (buttons)
        alert.addAction(UIAlertAction(title: "Continue", style: UIAlertAction.Style.default, handler: nil))
        alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertAction.Style.cancel, handler: nil))

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

三个按钮

class ViewController: UIViewController {

    @IBAction func showAlertButtonTapped(_ sender: UIButton) {

        // create the alert
        let alert = UIAlertController(title: "Notice", message: "Lauching this missile will destroy the entire universe. Is this what you intended to do?", preferredStyle: UIAlertController.Style.alert)

        // add the actions (buttons)
        alert.addAction(UIAlertAction(title: "Remind Me Tomorrow", style: UIAlertAction.Style.default, handler: nil))
        alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertAction.Style.cancel, handler: nil))
        alert.addAction(UIAlertAction(title: "Launch the Missile", style: UIAlertAction.Style.destructive, handler: nil))

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

处理按钮

在上面的例子中，处理程序为nil。当用户点击按钮时，你可以用一个闭包来替换nil。例如:

alert.addAction(UIAlertAction(title: "Launch the Missile", style: UIAlertAction.Style.destructive, handler: { action in

    // do something like...
    self.launchMissile()

}))

笔记

多个按钮不一定需要使用不同的UIAlertAction。风格类型。它们都可以是。default。 对于超过三个按钮，可以考虑使用动作表。设置非常相似。这里有一个例子。

斯威夫特有一个有趣的例子:

private func presentRandomJoke() {
  if let randomJoke: String = jokesController.randomJoke() {
    let alertController: UIAlertController = UIAlertController(title:nil, message:randomJoke, preferredStyle: UIAlertControllerStyle.Alert)
    alertController.addAction(UIAlertAction(title:"Done", style:UIAlertActionStyle.Default, handler:nil))
    presentViewController(alertController, animated:true, completion:nil)
  }
}