<% if elem.type? :collection_check_boxes %>
<%= elem.render(self, form) do |cb|%>
<%= cb.label class: 'form-check-label' do%>
<%= cb.check_box class: 'form-check-input' %> <%= cb.text %>
<%end%>
<%end%>
<% elsif elem.type? :collection_radio_buttons %>
<%= elem.render(self, form) do |cb|%>
<%= cb.label class: 'form-check-label' do%>
<%= cb.radio_button class: 'form-check-input' %> <%= cb.text %>
<%end%>
<%end%>
<% else %>
<%= elem.render(self, form, class_names('form-control', {'is-invalid': @record.errors[elem.proxy_field.name].any?})) %>
<% end %>