#101 Refactoring Out Helper Object

If you have complex view logic, this can easily lead to helper methods which call each other. See how to refactor this out into another object in this episode.

# application_helper.rb
def render_stars(rating)
  StarsRenderer.new(rating, self).render_stars
end

# helpers/stars_renderer.rb
class StarsRenderer
  def initialize(rating, template)
    @rating = rating
    @template = template
  end
  
  def render_stars
    content_tag :div, star_images, :class => 'stars'
  end

  private
  
  def star_images
    (0...5).map do |position|
      star_image(((@rating-position)*2).round)
    end.join
  end
  
  def star_image(value)
    image_tag "/images/#{star_type(value)}_star.gif", :size => '15x15'
  end
  
  def star_type(value)
    if value <= 0
      'empty'
    elsif value == 1
      'half'
    else
      'full'
    end
  end
  
  def method_missing(*args, &block)
    @template.send(*args, &block)
  end