A couple of helpers to generate dynamic forms in AJAX based on radio selections

SomeHelper.rb

module SomeHelper 
  # form:               Active form
  # question:           Text displayed as label
  # method:             The method to call
  # options:            A set of [value, label] pairs
  def radio_choice(form, question, method, options, onchange_fn = nil)
    html = question + "<br />"
    options.each do |option| 
       html << form.radio_button(method, option[0], :onchange => onchange_fn)
       html << form.label("#{method.to_s}_#{option[0]}", option[1])
    end
    html
  end
  
  # form:               Active form
  # question:           Text displayed as label
  # method:             The method to call
  # options:            A set of [value, label] pairs
  # condition:          The value for which the block is displayed
  # conditional_block:  The block to display when value of method is condition
  def radio_choice_with_conditional_block(form, question, method, options, condition, &conditional_block)
    html = radio_choice(form, question, method, options, blind_checker("#{form.object.class.name.downcase}_#{method.to_s}_#{condition}","#{method.to_s}_#{condition}_options"))
    html << "<div id='#{method.to_s}_#{condition}_options'"
    unless form.object[method] && form.object[method]==condition
      html << " style='display: none;' "
    end
    html << ">"
    concat(html)
    yield
    concat "</div>"
  end
  
private
  
  def blind_checker(check_element, blind_element)
    "if ($('" + check_element + "').checked) {" +
		visual_effect(:blind_down, blind_element, :duration => 0.3) +
		visual_effect(:highlight, blind_element) +
		"}else{" +
		visual_effect(:blind_up, blind_element, :duration => 0.3) +
		"}"
  end
end