Module: ActionView::Helpers::FormOptionsHelper

Includes:

ERB::Util

Included in:

ActionView::Helpers, InstanceTag

Defined in:

lib/action_view/helpers/form_options_helper.rb

Overview

Provides a number of methods for turning different kinds of containers into a set of option tags.

Options

The collection_select, country_select, select, and time_zone_select methods take an options parameter, a hash.

• :include_blank - set to true or a prompt string if the first option element of the select element is a blank. Useful if there is not a default value required for the select element.

For example,

select("post", "category", Post::CATEGORIES, {:include_blank => true})

could become:

joke poem

Another common case is a select tag for an belongs_to-associated object.

Example with @post.person_id => 2:

select("post", "person_id", Person.find(:all).collect {|p| [ p.name, p.id ] }, {:include_blank => 'None'})

could become:

None David Sam Tobias

• :prompt - set to true or a prompt string. When the select element doesn't have a value yet, this prepends an option with a generic prompt -- "Please select" -- or the given prompt string.

Example:

select("post", "person_id", Person.find(:all).collect {|p| [ p.name, p.id ] }, {:prompt => 'Select Person'})

could become:

Select Person David Sam Tobias

Like the other form helpers, select can accept an :index option to manually set the ID used in the resulting output. Unlike other helpers, select expects this option to be in the html_options parameter.

Example:

select("album[]", "genre", %w[rap rock country], {}, { :index => nil })

becomes:

rap rock country

Constant Summary

Constants included from ERB::Util

ERB::Util::HTML_ESCAPE, ERB::Util::JSON_ESCAPE

Instance Method Summary

• #collection_select(object, method, collection, value_method, text_method, options = {}, html_options = {}) ⇒ Object

  Returns and tags for the collection of existing return values of method for +object+'s class.

  #option_groups_from_collection_for_select(collection, group_method, group_label_method, option_key_method, option_value_method, selected_key = nil) ⇒ Object

  Returns a string of tags, like options_from_collection_for_select, but groups them by tags based on the object relationships of the arguments.

  #options_for_select(container, selected = nil) ⇒ Object

  Accepts a container (hash, array, enumerable, your type) and returns a string of option tags.

  #options_from_collection_for_select(collection, value_method, text_method, selected = nil) ⇒ Object

  Returns a string of option tags that have been compiled by iterating over the collection and assigning the the result of a call to the value_method as the option value and the text_method as the option text.

  #select(object, method, choices, options = {}, html_options = {}) ⇒ Object

  Create a select tag and a series of contained option tags for the provided object and method.

  #time_zone_options_for_select(selected = nil, priority_zones = nil, model = ::ActiveSupport::TimeZone) ⇒ Object

  Returns a string of option tags for pretty much any time zone in the world.

  #time_zone_select(object, method, priority_zones = nil, options = {}, html_options = {}) ⇒ Object

  Return select and option tags for the given object and method, using #time_zone_options_for_select to generate the list of option tags.

  Methods included from ERB::Util

  #html_escape, j, json_escape

  Instance Method Details

  #collection_select(object, method, collection, value_method, text_method, options = {}, html_options = {}) ⇒ Object

  Returns

  and tags for the collection of existing return values of method for +object+'s class. The value returned from calling method on the instance object will be selected. If calling method returns nil, no selection is made without including :prompt or :include_blank in the options hash.

  The :value_method and :text_method parameters are methods to be called on each member of collection. The return values are used as the value attribute and contents of each tag, respectively.

  Example object structure for use with this method:

  class Post < ActiveRecord::Base
  belongs_to :author
  end
  class Author < ActiveRecord::Base
  has_many :posts
  def name_with_initial
    "#{first_name.first}. #{last_name}"
  end
  end
  

  Sample usage (selecting the associated Author for an instance of Post, @post):

  collection_select(:post, :author_id, Author.find(:all), :id, :name_with_initial, {:prompt => true})
  

  If @post.author_id is already 1, this would return:

  <select name="post[author_id]">
  <option value="">Please select</option>
  <option value="1" selected="selected">D. Heinemeier Hansson</option>
  <option value="2">D. Thomas</option>
  <option value="3">M. Clark</option>
  </select>