StatusBarStyle

extension UISplitViewController {
    open override var childForStatusBarStyle: UIViewController? {
        return viewControllers.first
    }
}

extension UITabBarController {
    open override var childForStatusBarStyle: UIViewController? {
        return selectedViewController
    }
}

extension UINavigationController {
    open override var childForStatusBarStyle: UIViewController? {
        return viewControllers.last
    }
}