Question

In a simple form:

<%= form_for @user do |f| %>
  <%= f.label :source, "How did you find out about us?", :class => "control-label" %>
  <%= f.select(:source, options_for_select([['--  Please select  --',nil],['Source 1','Source 1'], ['Source 2','Source 2'], ['Other','Other']])) %>

  <%= f.label :source_other, "Specify Other Source" %>
  <%= f.text_field :source_other %>
<% end %>

I am trying to learn how to use JQuery to only show the “source_other” text field when the value “Other” is selected from the “source” field. From what I’ve seen online, it looks like I need to use something like this:

$("#source").change(function() {
  if ($("#source").val()=="Other")
    $("#source_other").show();
  else
    $("#source_other").hide();
});

However, I am not quite understanding how to integrate the JQuery with my form. Could someone please point me in the right direction?

Updated:

Here is the resulting html snippet:

<form accept-charset="UTF-8" action="/users" class="new_user" id="new_user" method="post">
  <label class="control-label" for="user_lead_source">How did you find out about us?</label>
  <select id="user_source" name="user[source]"><option value="">--  Please select  --</option>
    <option value="Source 1">Source 1</option>
    <option value="Source 2">Source 2</option>
    <option value="Other">Other</option>
  </select>

  <label for="user_source_other">Specify Other Source</label>
  <input id="user_source_other" name="user[source_other]" size="30" type="text" />
</form>

Answer 1

I am suspecting that your server code doesn’t generate an ID for the element, in which case your selectors are looking for elements with ID’s that don’t exist

If that is the case either add an ID with your server code so your jQuery ID selectors will work or use name= selectors

$(function(){
    $('input[name="source"]').change(function() {
      $('input[name="source_other"]').toggle(  $(this).val()=="Other" );

    });
});

As long as jQuery code is wrapped in $(document).ready() or $(function(){}); which is shorthand for same, you can place it anywhere in page in a script tag so long as it is after after jQuery library has loaded . Or you can put it in extrnal file that loads after jQuery