         }
     }
     
-    open weak var contentViewController : UIViewController? {
+    open weak var contentViewController: UIViewController? {
         willSet {
             if let contentViewController = self.contentViewController {
                 contentViewController.removeFromParentViewController()

        return super.shouldAutorotate
    }
    
    override open var supportedInterfaceOrientations : UIInterfaceOrientationMask {
        if let topViewController = self.topViewController() {
            return topViewController.supportedInterfaceOrientations
        }

    open var leftViewControllerVisible: Bool = false
    open var rightViewControllerVisible: Bool = false
    
    open weak var leftViewController: UIViewController? {
        willSet {
            if let leftViewController = self.leftViewController {
                leftViewController.removeFromParentViewController()
