“Disabled option tags in rails forms”

Update: My patch has now been accepted into core, which means that as of Rails 2.3, this plugin should no longer be necessary. More details here.

Ever wanted to disable options in a form select in rails? I have; it feels more useable to me to disable out of stock product sizes:

The rails Form Option Helpers won’t let you do this as they currently stand. So until things change in core, I’ve put together the option_tags_will_disable plugin.

Simply specify the disabled values when calling options_for_select:

<%= options_for_select(
  ['Choose a size', 'small', 'medium', 'large'],
  nil,     # selected value
  'medium' # disabled value
) %>
 
<!— Gives you —>
 
<option value="Choose a size">Please choose a size</option>
<option value="s">small</option>
<option value="m" disabled="disabled">medium</option>
<option value="l">large</option>
 

You can do the same when working with collections, but more interestingly, you can also give a Proc to identify which elements should be disabled:

<%= options_from_collection_for_select(
  @products,
  :id,
  :name,
  nil,                       # selected value(s)
  lambda{|p| !p.in_stock? }  # disabled value(s) identified with a proc 
) %>
 

And as an added bonus, selected options can also be identified with a Proc!