ios - 如何将 Controller 传递给函数

Question

你好，我有一个实用程序类，我在其中声明了这样的 AlertViewFunction

func displayAlertMessage(userMessage: String,//controller){
    let myAlert = UIAlertController(title: "Alert", message: userMessage, preferredStyle: UIAlertControllerStyle.Alert);
    let okAction =  UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default, handler: nil)
    myAlert.addAction(okAction);
    self.presentViewController(myAlert, animated: true, completion: nil)    
}

问题是我不能在这里使用self

self.presentViewController(myAlert, animated: true, completion: nil) 

我想将一个 Controller 传递给这个函数，这样我就可以像这样使用

controller.presentViewController(myAlert, animated: true, completion: nil) 

如何从任何 ViewController 传递 Controller 。假设我在 LoginViewController

Utility().displayAlertMessage(Message.INTERNETISNOTCONNECTED,//controller)

Answer 1

Utility().displayAlertMessage(Message.INTERNETISNOTCONNECTED, controller: self)

和

func displayAlertMessage(userMessage: String, controller: UIViewController)
{
    controller?.presentViewController(myAlert, animated: true, completion: nil)
}