gistfile1.rb

# Add this code to a new file and you can put it under app/admin/lib folder or else config/initializer/actice_admin.rb

module ActiveAdmin
  module Views
    class TableFor
      def html_column(attribute)
        column(attribute){ |model| model[attribute].html_safe }
      end

      def bool_column(attribute)
        column(attribute){ |model| model[attribute] ? '✔'.html_safe : '✗'.html_safe }
      end
    end

    class AttributesTable
      def html_row(attribute)
        row(attribute){ |model| model[attribute].html_safe }
      end

      def bool_row(attribute)
        row(attribute){ |model| model[attribute] ? '✔'.html_safe : '✗'.html_safe }
      end
    end
  end
end