Par d\u00e9faut, le m\u00e9lange de ces 3 ingr\u00e9dients ne fonctionne pas sous Rails.<\/p>\n
La solution est l\u00e0 :<\/p>\n
I dove into RoR Pagination yesterday (ActionController::Pagination), and while it\u2019s great for paginating all data in a model, it really sucks for paginating data from an activerecord association (and by really sucks I mean doesn\u2019t support).<\/p>\n
Here\u2019s the problem. Say I have a user who has a collection of photos:<\/p>\n
\r\nclass User < ActiveRecord::Base\r\nhas_many :photos, :conditions => 'photos.is_deleted = false', :order => 'photos.created_at DESC'\r\n\r\nend\r\n<\/code><\/pre>\nI want to have the ability to feed the user\u2019s photos to the paginator. Unfortunately, the
paginate<\/code> function simply takes a collection id, and will not accept a set of data (an association, in this case). So, if I want to paginate photos on a user, I have to do this:<\/p>\n\r\n@photo_pages, @photos = paginate :photos,\r\n:conditions => [\"photos.user_id=? AND is_deleted = false\", @user.id],\r\n:order => \"photos.created_at DESC\"\r\n<\/code><\/pre>\nWhat a mess. Now i\u2019ve lost the benefits of my association, since I have to define the association as part of the pagination rules. Very suprised Rails handles things this way, as it seems to violate the basic DRY principles. Anyways, I only had to write code like this a few times to realize how much of a pain in the ass it is, and I created a \u201cpaginate_association\u201d method to help me out.<\/p>\n
\r\ndef paginate_association(object, assoc_name, find_options = {}, per_page = 10)\r\npage = (params[:page] || 1).to_i\r\n\r\nitem_count = object.send(assoc_name.to_s + '_count')\r\noffset = (page-1)*per_page\r\n\r\n@items = object.send(assoc_name).find(:all, {:offset => offset, :limit => per_page}.merge(find_options))\r\n@item_pages = Paginator.new self, item_count, per_page, page\r\n\r\nreturn @item_pages, @items\r\nend\r\n<\/code><\/pre>\nI added this to my ApplicationController (application.rb), and now I can paginate assocations til the cows come home.<\/p>\n
\r\n@photo_pages, @photos = paginate_association @user, :photos, :order => 'created_at'\r\n<\/code><\/pre>\nThis helper uses the Rails Pagination stuff, so you can easily use
paginate<\/code> orpaginate_association<\/code> with the same view. Great!<\/p>\nYou can also pass additional \u201cfind\u201d arguments, such as
:order, :include, :join<\/code>, etc\u2026<\/p>\nHopefully this is as useful for you as it\u2019s been for me!<\/p><\/blockquote>\n
source<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
Par d\u00e9faut, le m\u00e9lange de ces 3 ingr\u00e9dients ne fonctionne pas sous Rails. La solution est l\u00e0 : I dove into RoR Pagination yesterday (ActionController::Pagination), and while it\u2019s great for paginating all data in a model, it really sucks for … Continue reading