class ActionView::Helpers::FormBuilder

#
# =>
radio_button("user", "receive_newsletter", "no")
radio_button("user", "receive_newsletter", "yes")

#
# =>
radio_button("post", "category", "java")
radio_button("post", "category", "rails")
# Let's say that @post.category returns "rails":

+options+ hash. You may pass HTML options there as well.
To force the radio button to be checked pass checked: true in the

radio button will be checked.
assigned to the template (identified by +object+). If the current value of +method+ is +tag_value+ the
Returns a radio button tag for accessing a specified attribute (identified by +method+) on an object

def radio_button(method, tag_value, options = {})
  @template.radio_button(@object_name, method, tag_value, objectify_options(options))
end