shuber-acts_as_tree

acts_as_tree

Specify this acts_as extension if you want to model a tree structure by providing parent and children associations

Installation

gem install shuber-acts_as_tree --source http://gems.github.com
OR
script/plugin install git://github.com/shuber/acts_as_tree.git

Usage

Requires a :foreign_key option which defaults to :parent_id

class Category < ActiveRecord::Base
  # schema
  #   id,        integer
  #   parent_id, integer
  #   name,      string
  
  acts_as_tree
end

Also accepts :order and :counter_cache (defaults to false) options

Example

root
  \_ child1
    \_ subchild1
    \_ subchild2

root      = Category.create(:name => 'root')
child1    = root.children.create(:name => 'child1')
subchild1 = child1.children.create(:name => 'subchild1')

root.parent   # nil
child1.parent # root
root.children # [child1]
root.children.first.children.first # subchild1

Copyright (c) 2007 David Heinemeier Hansson, released under the MIT license