I would like to disable the form submit button until all inputs have a value in them. My view has these inputs:

  <%= form_for @item, html: { enctype: "multipart/form-data", id: "upload-data" } do |f| %>
   <%= f.text_field :name %>
  <% end %>

I then run this validate() function with every keyup event:

$(document).ready(function() {
  validate();
  $('input').on('keyup', validate);
});

function validate() {
  var input = $('input');
  var isValid = false;
  $.each(input, function(k, v) {
    if (v.type != "submit") {
      isValid = (k == 0) ?
        v.value ? true : false : isValid && v.value ? true : false;
    }
    if (isValid) {
      $("input[type=submit]").prop("disabled", false);
    } else {
      $("input[type=submit]").prop("disabled", true);
    }
  });
}

Though the same code works here it does not work in my Rails view. It stays disabled. What am I overlooking?