     }
 
     private func vibrancyEffectView(forBlurEffectView blurEffectView:UIVisualEffectView) -> UIVisualEffectView {
-        let vibrancy = UIVibrancyEffect(forBlurEffect: blurEffectView.effect as UIBlurEffect)
+        let vibrancy = UIVibrancyEffect(forBlurEffect: blurEffectView.effect as! UIBlurEffect)
         let vibrancyView = UIVisualEffectView(effect: vibrancy)
         vibrancyView.frame = blurEffectView.bounds
         vibrancyView.autoresizingMask = .FlexibleWidth | .FlexibleHeight

        let statusBarVibrancyView = vibrancyEffectView(forBlurEffectView: statusBarBlurView)
        statusBarBlurView.contentView.addSubview(statusBarVibrancyView)

        let statusBar = UIApplication.sharedApplication().valueForKey("statusBar") as UIView
        statusBar.superview!.insertSubview(statusBarBlurView, belowSubview: statusBar)
        self.view.addSubview(statusBarBlurView)



extension ViewController: UIScrollViewDelegate {

    func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
        return scrollView.subviews.isEmpty ? nil : (scrollView.subviews[0] as! UIView)
    }

    func scrollViewDidZoom(scrollView: UIScrollView) {
        setContentInsetToCenterScrollView(scrollView)
    }

