 
   func collectionView(_ collectionView: UICollectionView,
                       numberOfItemsInSection section: Int) -> Int {
-    return colorSchemeCells.count
+    return colorSchemeConfigurations.count
   }
 
   func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
-    let colorScheme = colorSchemeCells[indexPath.item].colorScheme
+    let colorScheme = colorSchemeConfigurations[indexPath.item].colorScheme()
     navigationController?.popViewController(animated: true)
-    AppTheme.globalTheme = AppTheme(colorScheme: colorScheme(),
+    AppTheme.globalTheme = AppTheme(colorScheme: colorScheme,
                                     typographyScheme: AppTheme.globalTheme.typographyScheme)
   }
 

  return scheme
}

class MDCThemePickerViewController: UIViewController, UICollectionViewDataSource,
  UICollectionViewDelegateFlowLayout {


  override func viewDidLoad() {
    super.viewDidLoad()

    paletteTitle.text = "Material Palette-based themes"
    paletteTitle.font = titleFont
    paletteTitle.textColor = titleColor
    paletteTitle.translatesAutoresizingMaskIntoConstraints = false
