 
     public var selectedIndex: Int? = 0 {
         didSet {
-            
+            let animated = revealed
+            if let index = selectedIndex {
+                collectionView.selectItemAtIndexPath(
+                    NSIndexPath(forItem: index, inSection: 0),
+                    animated: animated,
+                    scrollPosition:.CenteredHorizontally
+                )
+            } else {
+                collectionView.selectItemAtIndexPath(nil, animated: animated, scrollPosition: .CenteredHorizontally)
+            }
         }
     }
     

        super.commonInit()
        
        backgroundColor = UIColor(red: 51.0 / 255.0, green: 51.0 / 255.0, blue: 75.0 / 255.0, alpha: 1.0)
    }
    
    public override init(frame: CGRect = CGRect(x: 0.0, y: 0.0, width: 320.0, height: DefaultContentHeight)) {

    // MARK: - CollectionView
    private lazy var collectionView: UICollectionView = { [unowned self] in
        let view = UICollectionView(frame: CGRectZero, collectionViewLayout: self.collectionLayout)
        view.clipsToBounds = false
        view.backgroundColor = UIColor.clearColor()
        view.showsHorizontalScrollIndicator = false
        view.registerClass(MenuCell.self, forCellWithReuseIdentifier: CellIdentifier)
