     }
     
     func addLeftPanelViewController() {
-        if (leftViewController == nil) {
+        if leftViewController == nil {
             leftViewController = UIStoryboard.leftViewController()
             
             addChildSidePanelController(leftViewController!)

    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.configureBlurView()
        mainViewController = UIStoryboard.mainViewController()
        centerNavigationController = UINavigationController(rootViewController: mainViewController)
        centerNavigationController.setNavigationBarHidden(true , animated: false)

    var centerNavigationController: UINavigationController!
    var mainViewController: MainTabBarController!
    var leftViewController: SlidePanelViewController?
    
    var currentState: SlideOutState = .collapsed {
        didSet {
            let shouldShowShadow = currentState != .collapsed
