Will Paginate view helpers

Renders a helpful message with numbers of displayed vs. total entries. You can use this as a blueprint for your own, similar helpers.

<%= page_entries_info @posts %>
#-> Displaying posts 6 - 10 of 26 in total

By default, the message will use the humanized class name of objects in collection: for instance, “project types” for ProjectType models. Override this with the :entry_name parameter:

<%= page_entries_info @posts, :entry_name => 'item' %>
#-> Displaying items 6 - 10 of 26 in total

# File lib/will_paginate/view_helpers.rb, line 167
    def page_entries_info(collection, options = {})
      entry_name = options[:entry_name] ||
        (collection.empty?? 'entry' : collection.first.class.name.underscore.sub('_', ' '))
      
      if collection.total_pages < 2
        case collection.size
        when 0; "No #{entry_name.pluralize} found"
        when 1; "Displaying <b>1</b> #{entry_name}"
        else;   "Displaying <b>all #{collection.size}</b> #{entry_name.pluralize}"
        end
      else
        %{Displaying #{entry_name.pluralize} <b>%d&nbsp;-&nbsp;%d</b> of <b>%d</b> in total} % [
          collection.offset + 1,
          collection.offset + collection.length,
          collection.total_entries
        ]
      end
    end

Wrapper for rendering pagination links at both top and bottom of a block of content.

<% paginated_section @posts do %>
  <ol id="posts">
    <% for post in @posts %>
      <li> ... </li>
    <% end %>
  </ol>
<% end %>

will result in:

<div class="pagination"> ... </div>
<ol id="posts">
  ...
</ol>
<div class="pagination"> ... </div>

Arguments are passed to a will_paginate call, so the same options apply. Don’t use the :id option; otherwise you’ll finish with two blocks of pagination links sharing the same ID (which is invalid HTML).

# File lib/will_paginate/view_helpers.rb, line 142
    def paginated_section(*args, &block)
      pagination = will_paginate(*args).to_s
      
      unless ActionView::Base.respond_to? :erb_variable
        concat pagination
        yield
        concat pagination
      else
        content = pagination + capture(&block) + pagination
        concat(content, block.binding)
      end
    end

Renders Digg/Flickr-style pagination for a WillPaginate::Collection object. Nil is returned if there is only one page in total; no point in rendering the pagination in that case...

Options

Display options:

• :previous_label — default: “« Previous” (this parameter is called :prev_label in versions 2.3.2 and older!)
• :next_label — default: “Next »“
• :page_links — when false, only previous/next links are rendered (default: true)
• :inner_window — how many links are shown around the current page (default: 4)
• :outer_window — how many links are around the first and the last page (default: 1)
• :separator — string separator for page HTML elements (default: single space)

HTML options:

• :class — CSS class name for the generated DIV (default: “pagination”)
• :container — toggles rendering of the DIV container for pagination links, set to false only when you are rendering your own pagination markup (default: true)
• :id — HTML ID for the container (default: nil). Pass true to have the ID automatically generated from the class name of objects in collection: for example, paginating ArticleComment models would yield an ID of “article_comments_pagination“.

Advanced options:

• :param_name — parameter name for page number in URLs (default: :page)
• :params — additional parameters when generating pagination links (eg. :controller => "foo", :action => nil)
• :renderer — class name, class or instance of a link renderer (default: WillPaginate::LinkRenderer)

All options not recognized by will_paginate will become HTML attributes on the container element for pagination links (the DIV). For example:

<%= will_paginate @posts, :style => 'font-size: small' %>

… will result in:

<div class="pagination" style="font-size: small"> ... </div>

Using the helper without arguments

If the helper is called without passing in the collection object, it will try to read from the instance variable inferred by the controller name. For example, calling will_paginate while the current controller is PostsController will result in trying to read from the @posts variable. Example:

<%= will_paginate :id => true %>

… will result in @post collection getting paginated:

<div class="pagination" id="posts_pagination"> ... </div>

# File lib/will_paginate/view_helpers.rb, line 89
    def will_paginate(collection = nil, options = {})
      options, collection = collection, nil if collection.is_a? Hash
      unless collection or !controller
        collection_name = "@#{controller.controller_name}"
        collection = instance_variable_get(collection_name)
        raise ArgumentError, "The #{collection_name} variable appears to be empty. Did you " +
          "forget to pass the collection object for will_paginate?" unless collection
      end
      # early exit if there is nothing to render
      return nil unless WillPaginate::ViewHelpers.total_pages_for_collection(collection) > 1
      
      options = options.symbolize_keys.reverse_merge WillPaginate::ViewHelpers.pagination_options
      if options[:prev_label]
        WillPaginate::Deprecation::warn(":prev_label view parameter is now :previous_label; the old name has been deprecated", caller)
        options[:previous_label] = options.delete(:prev_label)
      end
      
      # get the renderer instance
      renderer = case options[:renderer]
      when String
        options[:renderer].to_s.constantize.new
      when Class
        options[:renderer].new
      else
        options[:renderer]
      end
      # render HTML for pagination
      renderer.prepare collection, options, self
      renderer.to_html
    end