Warning: Attempt to present * on * whose view is not in the window hierarchy - swift

Question

I\'m trying to present a ViewController if there is any saved data in the data model. But I get the following error:

Warning: A

Answer 1

For swift 3.0 and above

public static func getTopViewController() -> UIViewController?{
if var topController = UIApplication.shared.keyWindow?.rootViewController
{
  while (topController.presentedViewController != nil)
  {
    topController = topController.presentedViewController!
  }
  return topController
}
return nil}