Swap rootViewController with animation? : <p>Im trying to swap to another root view controller with a tab bar; via app delegate, and I want to add transition animation. By default it would only show the view without any animation.</p>

<pre><code>let tabBar = self.instantiateViewController(storyBoard: "Main", viewControllerID: "MainTabbar")
let appDelegate = UIApplication.shared.delegate as! AppDelegate
appDelegate.window = UIWindow(frame: UIScreen.main.bounds)
appDelegate.window?.rootViewController = tabBar
appDelegate.window?.makeKeyAndVisible()
</code></pre>

<p>That's how I swapped to another rootview controller.</p>
