Extends ActiveRecord attributes with a :choices pseudo-type that provides convenient methods for mapping each choice to its human readable form.

By defining the available choices for the gender attribute in your User model,

class User < ActiveRecord::Base
  attribute_choices :gender,  [ ['m', "Male"], ['f', 'Female'] ], 
                              :validate => true
end

...for any given User instance,

@john = User.new(:gender => 'm')
@john.gender
 => 'm'

...you can access the human readable attribute value like this:

@john.gender_display
 => 'Male'

If you need to provide the available choices in a select tag, you can simply use User#gender_choices,

<%= select("user", "gender", User.gender_choices) %>

...which would give you the following HTML snippet

<select name="user[gender]">
  <option value="m">Male</option>
  <option value="f">Femail</option>
</select>

Validation is also taken care of, if you specify :validate => true in the options

 @john.gender = 'x'
 @john.valid? 
  => false

And if you work with multiple languages, given the following es.yml

es:
  user:
    gender_choices:
      male:  'Hombre
      female: 'Mujer'

...you can specify the attribute choices like this:

class User < ActiveRecord::Base
  attribute_choices :gender,  [ ['m', 'user.gender_choices.male'], ['f', 'user.gender_choices.female'] ], 
                              :validate => true, :localize => true
end

Then, provided that I18n.locale == :es, you are good to go:

@john.gender_display
 => 'Hombre'

User.gender_choices
  => [["Hombre", 'm'], ['Mujer', 'f']]

In your Gemfile add

gem 'attribute_choices'

In environment.rb add:

config.gem 'attribute_choices'

• Works correctly with overridden ActiveRecord attribute accessors
• Multi-ruby integration testing with Travis-CI

• Refactor to eliminate deprecation warnings in Rails 3.1 (@porras)

• Initial release

• Validate absence of _display and _choices methods

Copyright (c) 2009-2011 Christos Zisopoulos, released under the MIT license