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

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

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

Relevant code:

override func viewDidLoad() {
    super.viewDidLoad()
    loginButton.backgroundColor = UIColor.orangeColor()

    var request = NSFetchRequest(entityName: "UserData")
    request.returnsObjectsAsFaults = false

    var appDel:AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
    var context:NSManagedObjectContext = appDel.managedObjectContext!

    var results:NSArray = context.executeFetchRequest(request, error: nil)!

    if(results.count <= 0){
        print("Inga resultat")
    } else {
        print("SWITCH VIEW PLOX")
        let internVC = self.storyboard?.instantiateViewControllerWithIdentifier("internVC") as internViewController
        self.presentViewController(internVC, animated: true, completion: nil)
    }
}

I've tried different solutions found using Google without success.

At this point in your code the view controller's view has only been created but not added to any view hierarchy. If you want to present from that view controller as soon as possible you should do it in viewDidAppear to be safest.

In objective c: This solved my problem when presenting viewcontroller on top of mpmovieplayer

- (UIViewController*) topMostController
{
    UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;

    while (topController.presentedViewController) {
        topController = topController.presentedViewController;
    }

    return topController;
}

Swift 3

I had this keep coming up as a newbie and found that present loads modal views that can be dismissed but switching to root controller is best if you don't need to show a modal.

I was using this

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc  = storyboard?.instantiateViewController(withIdentifier: "MainAppStoryboard") as! TabbarController
present(vc, animated: false, completion: nil)

Using this instead with my tabController:

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let view = storyboard.instantiateViewController(withIdentifier: "MainAppStoryboard") as UIViewController
let appDelegate = UIApplication.shared.delegate as! AppDelegate
//show window
appDelegate.window?.rootViewController = view

Just adjust to a view controller if you need to switch between multiple storyboard screens.