Module: OrderedTree

Defined in:
lib/ordered_tree.rb,
lib/ordered_tree/class_methods.rb,
lib/ordered_tree/instance_methods.rb,
lib/ordered_tree/instance_methods/list.rb,
lib/ordered_tree/instance_methods/misc.rb,
lib/ordered_tree/instance_methods/tree.rb,
lib/ordered_tree/instance_methods/destroy.rb

Overview

:nodoc:

Defined Under Namespace

Modules: ClassMethods, InstanceMethods

Instance Method Summary collapse

Instance Method Details

#ordered_tree(options = {}) ⇒ Object

Configuration:

class Person < ActiveRecord::Base
  ordered_tree :foreign_key   => :parent_id,
               :order         => :position
end

class CreatePeople < ActiveRecord::Migration
  def self.up
    create_table :people do |t|
      t.column :parent_id ,:integer ,:null => false ,:default => 0
      t.column :position  ,:integer
    end
    add_index(:people, :parent_id)
  end
end



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# File 'lib/ordered_tree.rb', line 22

def ordered_tree(options = {})
  cattr_accessor :ordered_tree_config
  self.ordered_tree_config ||= {}
  self.ordered_tree_config[:foreign_key] ||= :parent_id
  self.ordered_tree_config[:order] ||= :position
  self.ordered_tree_config.update(options) if options.is_a?(Hash)

  belongs_to :parent_node, :class_name => self.name, :foreign_key => ordered_tree_config[:foreign_key]
  has_many :child_nodes, :class_name => self.name, :foreign_key => ordered_tree_config[:foreign_key], :order => ordered_tree_config[:order]
  scope :roots, lambda { |*args|
    scope_condition = args[0]
    where(scope_condition).where(self.ordered_tree_config[:foreign_key].to_sym => 0).order(self.ordered_tree_config[:order])
  }

  # If the scope is something like :person, then turn it into :person_id
  if self.ordered_tree_config[:scope].is_a?(Symbol) && self.ordered_tree_config[:scope].to_s !~ /_id$/
    self.ordered_tree_config[:scope] = "#{self.ordered_tree_config[:scope]}_id".intern
  end

  if self.ordered_tree_config[:scope].is_a?(Symbol) # ie :person_id
    define_method "scope_condition" do
      hash = {self.class.ordered_tree_config[:scope].to_sym => send(self.class.ordered_tree_config[:scope].to_sym)}
      self.class.send(:sanitize_sql_hash_for_conditions, hash)
    end
  end

  include OrderedTree::ClassMethods
  include OrderedTree::InstanceMethods
end