def radio_button(name, identifier={:index => 0}, &block)
      standard_methods(name, identifier, 'radio_button_for', &block)
      define_method("select_#{name}") do
        return platform.select_radio(identifier.clone) unless block_given?
        self.send("#{name}_element").select
      end
      define_method("#{name}_selected?") do
        return platform.radio_selected?(identifier.clone) unless block_given?
        self.send("#{name}_element").selected?
      end
    end
def radio_button(name, identifier={:index => 0}, &block)
      standard_methods(name, identifier, 'radio_button_for', &block)
      define_method("select_#{name}") do
        return platform.select_radio(identifier.clone) unless block_given?
        self.send("#{name}_element").select
      end
      define_method("#{name}_selected?") do
        return platform.radio_selected?(identifier.clone) unless block_given?
        self.send("#{name}_element").selected?
      end
    end
adds four methods - one to select, another to return if a radio button
 is selected, another method to return a PageObject::Elements::RadioButton
 object representing the radio button element, and another to check
 the radio button's existence.

 @example
   radio_button(:north, :id => "north")
   # will generate 'select_north', 'north_selected?',
   # 'north_element', and 'north?' methods

 @param [Symbol] the name used for the generated methods
 @param [Hash] identifier how we find a radio button.
 @param optional block to be invoked when element method is called