Printerest like CollectionView renderer for iOS in Xamarin.Forms?

After some research I could find the custom renderer for CollectionView in Android and it works great, but I couldn't find the equalant for iOS. Please help me create it for iOS. Thanks

Custom CollectionView for android:

[assembly: ExportRenderer(typeof(CollectionView), typeof(CustomCollectionViewRenderer))]
namespace App.Droid
{
    public class CustomCollectionViewRenderer : CollectionViewRenderer
    {
        public CustomCollectionViewRenderer(Context context) : base(context)
        {
        }

        protected override void OnElementChanged(ElementChangedEventArgs<ItemsView> elementChangedEvent)
        {
            base.OnElementChanged(elementChangedEvent);

            if (elementChangedEvent.NewElement != null)
            {
                StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager(3, StaggeredGridLayoutManager.Vertical);
                SetLayoutManager(manager);
            }
        }
    }
}

Custom CollectionView for iOS: ??