public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
        {
            View           itemView = LayoutInflater.From(parent.Context).Inflate(Resource.Layout.Chemical, parent, false);
            ChemicalHolder vh       = new ChemicalHolder(itemView);

            return(vh);
        }
 public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int position)
 {
     ChemicalHolder vh = holder as ChemicalHolder;
     var chemical = _items[position];
     vh.Image.SetImageResource(chemical.DrawableId);
     vh.Caption.Text = chemical.Name;
 }