re render fields_for with ajax - ruby-on-rails-3

Question

I have a problem refreshing a partial with fields_for inside.
Here is the code of the partial ('table_detalle')
<table class="table">
<thead>
<tr>
<th><%= t('.denominacion') %></th>
<th><%= t('.cantidad_ingreso') %></th>
<th><%= t('.importe') %></th>
</tr>
</thead>
<tbody>
<%= f.fields_for :operacion_detalles do |builder| %>
<tr>
<%= render 'table_detalle_operacion', f: builder %>
</tr>
<% end unless #operacion.nil? %>
</tbody>
</table>
<%= content_tag :h3, t('.total', :value=> number_to_currency(#operacion.R_IMPORTE)).html_safe, :class => 'pull-right', style: 'display:inline' %>
when the user change a value of a combo i would like to refresh the partial above (because the details objects must change and are editable)
Here is the javascript code:
$('#operacion_TIPOVALOR_ID').change(function(){
$.ajax({
url: '<%= cambiar_tipo_valor_movimientos_path %>',
data: {tipo_valor_id: $('#operacion_TIPOVALOR_ID').val()},
complete: function(){
$('#tipo_valor_loader').css('display','none');
},
beforeSend: function(){
$('#tipo_valor_loader').css('display','inline');
},
success: null,
dataType: 'script'
});
});
the controller code:
def cambiar_tipo_valor
#operacion = Operacion.new
denominaciones = TipoValorDenominacion.all_from_tipo_valor params[:tipo_valor_id]
denominaciones.each do |deno|
#operacion.operacion_detalles.build :tipo_valor_denominacion => deno, :I_CANTIDAD => 0, :R_IMPORTE => 0
end
end
as you can see the "operacion_detalles" change depending on the user selection.
the .js.erb code:
$('#detalle').html('<%= escape_javascript(render :partial => 'table_detalle') %>');
But, i get:
undefined local variable or method `f' for #<#<Class:0x45ae1c8>:0x5062338>
So, i need the f variable to render the partial. Is there any way to emulate the f variable?
Thanks in advance.

Answer 1

I had no other choice than resolve the problem by hand. What i mean?
Instead of a field_for => each_with_index:
<% #operacion.operacion_detalles.each_with_index do |detalle, index| %>
<tr>
<%= render 'table_detalle_operacion', detalle: detalle, index: index %>
</tr>
<% end -%>
The use the tags helpers like this:
<td>
<input type="hidden" value="<%= detalle.tipo_valor_denominacion.R_MULTIPLICADOR %>" class="multiplicador"/>
<%= hidden_field_tag "operacion[operacion_detalles_attributes][#{index}][TIPOVALORDENO_ID]", detalle.TIPOVALORDENO_ID %>
<%= detalle.tipo_valor_denominacion.CTIPOVALORDENO %></td>
<td>
<%= text_field_tag "operacion[operacion_detalles_attributes][#{index}][I_CANTIDAD]", detalle.I_CANTIDAD %>
<%= content_tag(:span, detalle.errors[:I_CANTIDAD].join(', '), class: 'help-block') if detalle.errors.has_key? :I_CANTIDAD %>
</td>
<td>
<%= hidden_field_tag "operacion[operacion_detalles_attributes][#{index}][R_IMPORTE]", detalle.R_IMPORTE %>
<%= content_tag :span, number_to_currency(detalle.R_IMPORTE), class: 'detalle-importe pull-right' %>
<%= content_tag(:span, detalle.errors[:R_IMPORTE].join(', '), class: 'help-block') if detalle.errors.has_key? :R_IMPORTE %>
</td>
In this case i had supply the names, so when this code is executed
$('#detalle').html('<%= escape_javascript(render :partial => 'table_detalle') %>')
It does not need the f variable.
Hope it helps.
pd: I know this is not a very good solution but it works.