<%= f.select :domain, domain_options, required: true %>
<% Quantity.domains.each_key do |d| %>
<%= f.select :parent_id, parent_options(d),
{required: true, label: :field_parent_quantity} %>
<% end %>
<%= f.text_field :name, size: 25, required: true %>
<%= f.text_field :description, size: 200 %>
<%= f.text_field :formula, size: 200, placeholder: t('.formula_placeholder') %>
<%= f.check_box :primary %>
<%= javascript_tag do %>
function domainChange() {
$('[id^=parent_select_]').prop('disabled', true).hide();
$('[id^=parent_select_] select').attr('name', 'placeholder');
$('[id=parent_select_'+$('#quantity_domain option:selected').val()+']')
.prop('disabled', false).show();
$('[id=parent_select_'+$('#quantity_domain option:selected').val()+'] select')
.attr('name', 'quantity[parent_id]');
}
$('#quantity-form').on('click', '#quantity_domain', domainChange);
$(document).ready(function() {
domainChange();
});
<% end %>