Cancel Button in UIAlertController with UIAlertControllerStyle.ActionSheet

I wanted to go ahead and provide a specific answer for a specific question. The user asked about the implementation of a "cancel" button, not a default button. Check out the answer below!

let alertController = UIAlertController(title: "Select one", message: "Hey! Press a button", preferredStyle: .actionSheet)

let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

alertController.addAction(cancelAction)

self.present(alertController, animated: true, completion: nil)

Its really simple, but works a bit differently to how they used to work. Now you add "actions" to your alerts. These actions are then represented by buttons on the device.

alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))

Above is the code needed for a simple cancel button - bear in mind that dismissal of the alert is done automatically so don't put that in your handler. Should you then want to create another button which does something, use the code below:

alert.addAction(UIAlertAction(title: "Button", style: UIAlertActionStyle.Default, handler: { action in
        println("This button now calls anything inside here!")
    }))

Hopefully I have understood your question and this answers what you were asking. I will also add that after you have added all of the "actions", you present the alert using the code below:

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

Hope this helps!