active admin custom class for td

table_for.rb

module ActiveAdmin
  module Views
    class TableFor < Arbre::HTML::Table


      def build_table_cell(col, item)


        td(:class => ( col.options[:class] || (col.data.to_s.downcase if col.data.is_a?(Symbol))))  do
          rvalue = call_method_or_proc_on(item, col.data, :exec => false)
          if col.data.is_a?(Symbol)
            rvalue = pretty_format(rvalue)
          end
          rvalue
        end
      end
      class Column
        attr_accessor :options
      end

    end
  end
end