   override func viewDidLoad() {
     super.viewDidLoad()
 
-    inkController.addInkView()
+    rippleController.addRipple(to: self.collectionView!)
 
     let containerView = UIView(frame: headerViewController.headerView.bounds)
     containerView.autoresizingMask = [.flexibleWidth, .flexibleHeight]

  override func collectionView(_ collectionView: UICollectionView,
                               cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell =
        collectionView.dequeueReusableCell(withReuseIdentifier: "MDCCatalogCollectionViewCell",
                                           for: indexPath)
    cell.backgroundColor = AppTheme.containerScheme.colorScheme.backgroundColor

    let componentName = node.children[indexPath.row].title

    return node.children.count
  }

  // MARK: MDCRippleTouchControllerDelegate

  func rippleTouchController(
    _ rippleTouchController: MDCRippleTouchController,
    shouldProcessRippleTouchesAtTouchLocation location: CGPoint
  ) -> Bool {
    return self.collectionView?.indexPathForItem(at: location) != nil
  }

  func rippleTouchController(
    _ rippleTouchController: MDCRippleTouchController,
    rippleViewAtTouchLocation location: CGPoint
  ) -> MDCRippleView? {
    if let indexPath = self.collectionView?.indexPathForItem(at: location) {
      let cell = self.collectionView?.cellForItem(at: indexPath)
      return MDCRippleView.injectedRippleView(for: cell!)
    }
    return MDCRippleView()
  }

  // MARK: UICollectionViewDelegate
