Form not submitting hidden input

Question

There is hidden input in code which must be TRY by default and be changeable using dropdown box. Code: HTML:

Answer 1

As Backbone Binder can't see hidden changes in hidden inputs they mustn't change in page. It can be solved by adding trigger('change'); to the code:

$('.js-listing-price-currency').val($(this).data('value')).trigger('change');