AlertView for Swift (iOS)

gistfile1.swift

if self.reviews.count == 0 {
  var alert = UIAlertController(title: "Whoops...", message: "No reviews yet!", preferredStyle: UIAlertControllerStyle.Alert)
  alert.addAction(UIAlertAction(title: "Okay",
    style: UIAlertActionStyle.Default, handler: {(alert: UIAlertAction!) in
      self.navigationController?.popViewControllerAnimated(true)
      return //force return since popViewControllerAnimated(true) returns a ViewController instead of void
    }))
  
  //alternative action
  /*alert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: { action in
    switch action.style{
      case .Default:
        self.navigationController?.popViewControllerAnimated(true)
                            
      case .Cancel:
        println("cancel")
                            
      case .Destructive:
        println("destructive")
    }
  }))*/
  
  self.presentViewController(alert, animated: true, completion: nil)
}