             drawerState     = _panDelta < 0 ? .Closed : .Opened
             constant        = min(_drawerConstraint.constant + delta, drawerWidth)
             backGroundAlpha = min(
-                _kContainerViewMaxAlpha,
-                _kContainerViewMaxAlpha*(abs(constant)/drawerWidth)
+                containerViewMaxAlpha,
+                containerViewMaxAlpha*(abs(constant)/drawerWidth)
             )
         case .Right:
             drawerState     = _panDelta > 0 ? .Closed : .Opened
             constant        = max(_drawerConstraint.constant + delta, -drawerWidth)
             backGroundAlpha = min(
-                _kContainerViewMaxAlpha,
-                _kContainerViewMaxAlpha*(abs(constant)/drawerWidth)
+                containerViewMaxAlpha,
+                containerViewMaxAlpha*(abs(constant)/drawerWidth)
             )
         }
         

                    self._drawerConstraint.constant     = constant
                    self._containerView.backgroundColor = UIColor(
                        white: 0
                        , alpha: self._kContainerViewMaxAlpha
                    )
                }
                self._containerView.layoutIfNeeded()

    @objc public enum DrawerState: Int {
        case Opened, Closed
    }

    /**************************************************************************/
    // MARK: - Properties
    /**************************************************************************/

    @IBInspectable public var containerViewMaxAlpha: CGFloat = 0.2

    @IBInspectable public var drawerAnimationDuration: NSTimeInterval = 0.25

    @IBInspectable public var mainSegueIdentifier: String?
    
    @IBInspectable public var drawerSegueIdentifier: String?
