ruby on rails f.select options with custom attributes

Question

I have a form select statement, like this:

= f.select :country_id, @countries.map{ |c| [c.name, c.id] }

Which results in this code:

Answer 1

The extra attributes hash is only supported in Rails 3.

If you're on Rails 2.x, and want to override options_for_select

I basically just copied the Rails 3 code. You need to override these 3 methods:

def options_for_select(container, selected = nil)
    return container if String === container
    container = container.to_a if Hash === container
    selected, disabled = extract_selected_and_disabled(selected)

    options_for_select = container.inject([]) do |options, element|
      html_attributes = option_html_attributes(element)
      text, value = option_text_and_value(element)
      selected_attribute = ' selected="selected"' if option_value_selected?(value, selected)
      disabled_attribute = ' disabled="disabled"' if disabled && option_value_selected?(value, disabled)
      options << %(#{html_escape(text.to_s)})
    end

    options_for_select.join("\n").html_safe
end

def option_text_and_value(option)
  # Options are [text, value] pairs or strings used for both.
  case
  when Array === option
    option = option.reject { |e| Hash === e }
    [option.first, option.last]
  when !option.is_a?(String) && option.respond_to?(:first) && option.respond_to?(:last)
    [option.first, option.last]
  else
    [option, option]
  end
end

def option_html_attributes(element)
  return "" unless Array === element
  html_attributes = []
  element.select { |e| Hash === e }.reduce({}, :merge).each do |k, v|
    html_attributes << " #{k}=\"#{ERB::Util.html_escape(v.to_s)}\""
  end
  html_attributes.join
end

Kinda messy but it's an option. I place this code in a helper module called RailsOverrides which I then include in ApplicationHelper. You can also do a plugin/gem if you prefer.

One gotcha is that to take advantage of these methods you must always invoke options_for_select directly. Shortcuts like

select("post", "person_id", Person.all.collect {|p| [ p.name, p.id, {"data-stuff"=>"html5"} ] })

will yield the old results. Instead it should be:

select("post", "person_id", options_for_select(Person.all.collect {|p| [ p.name, p.id, {"data-stuff"=>"html5"} ] }))

Again not a great solution, but it might be worth it to get to the ever so useful data-attribute.