will_paginate nested object in Rails

I have a model that has the following association:

class Tournament < ActiveRecord::Base
has_one :gallery, dependent: :destroy
has_many :gallery_images, :through => :gallery, dependent: :destroy
end

I would like to paginate just the gallery_images as opposed to the tournament itself but as I am getting the gallery_images as a nested attribute I'm not sure how to do this using will_paginate

Controller

def galleries
  @tournaments = Tournament.all
  #tried this
  @gallery_images = @tournaments.gallery_images.paginate(:page => params[:page], :per_page => 9)
end

View

                 <% @tournaments.each do |t| %>
                    <div>
                        <div class="clear"></div>
                          <ul class="team-gallery">
                            <% t.gallery_images.each do |g| %>
                              <li>
                                <%= link_to image_tag(g.photo.url(:gallery_large)), g.photo.url(:gallery_large), class: 'clb-photo' %> 
                              </li>
                            <% end %>
                        </ul>
                     </div>

How can I paginate just the t.gallery_images?

Solution

Are you sure this is working code?

@gallery_images = @tournaments.gallery_images.paginate(:page => params[:page], :per_page => 9)

You are calling gallery_images, what appears to be an instance method, on an ActiveRecord collection, which is essentially an array. That won't work.

I suspect you want to loop over the tournaments and call paginate on the images of each tournament.

<% @tournaments.each do |t| %>
  <%= will_paginate t.gallery_images.paginate(page: params[:page], per_page: 9) %>
<% end %>

You can create an instance method on the Tournament model to save you from writing all that each time you want to paginate tournament images.

class Tournament
  def paginated_images(page, per_page = 9)
    gallery_images.paginate(page: page, per_page: per_page)
  end
end

Then you can do this in your view:

<% @tournaments.each do |t| %>
  <% images = t.paginated_images(params[:page]) %>
  <% images.each do |image| %>
    <%= image_tag image %>
  <% end %>
  <%= will_paginate images %>
<% end %>