Paginator

Paginator is a simple pagination class that provides a generic interface suitable for use in any Ruby program.

Paginator doesn't make any assumptions as to how data is retrieved; you just have to provide it with the total number of objects and a way to pull a specific set of objects based on the offset and number of objects per page.

In both of these examples I'm using a PER_PAGE constant (the number of items per page), but it's merely for labeling purposes.

You could, of course, just pass in the number of items per page directly to the initializer without assigning it somewhere beforehand.

bunch_o_data = (1..60).to_a
pager = Paginator.create(bunch_o_data.size, PER_PAGE) do |offset, per_page|
  bunch_o_data[offset,per_page]
end
pager.each do |page|
  puts "Page ##{page.number}"
  page.each do |item|
    puts item
  end
end

Nothing changes with Paginator; you just use ActiveRecord from within the block you provide.

A controller action:

def index
  @pager = Paginator.create(Foo.count, PER_PAGE) do |offset, per_page|
    Foo.limit(per_page).offset(offset)
  end
  @page = @pager.page(params[:page])
end

In your view:

<% @page.each do |foo| %>
  <%# Show something for each item %>
<% end %>
<%= @page.number %>
<%= link_to("Prev", foos_url(page: @page.prev.number)) if @page.prev? %>
<%= link_to("Next", foos_url(page: @page.next.number)) if @page.next? %>

See LICENSE.txt.