IOS crash when set sidemenu as rootviewcontroller

[hafiz013]

when i set sidemenu as rootview controller it is crash. Below here my sample code:

let mainScreen = storyboard.instantiateViewController(withIdentifier: "SideMenu") as! SideMenuController
                let homeNavigationController = UINavigationController(rootViewController: mainScreen)
                self.window?.rootViewController = homeNavigationController
                self.window?.makeKeyAndVisible()`

log cat errror:

menuViewController.beginAppearanceTransition(true, animated: true). <-- Thread 1: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value

Why?

[kukushi]

@hafiz013 Can you provide functional code for reproducing this issue?