Navigation bar hides when using popToRootViewControllerAnimated in swift?

Question

In my App, I have to redirect users to my rootview from my login screen.

I used popViewControllerAnimated it just pops only one view.

So i am using popToRootViewControllerAnimated. But when i am doing it the Navigation bar hides. I referred some links like this & implemented it. But it is of no use.

Tried Code

override func viewDidAppear(animated: Bool)
{
    self.navigationController?.navigationBarHidden = false
}

Thanks in advance!