annotate vendor/plugins/awesome_nested_set/README.rdoc @ 1082:997f6d7738f7 bug_531

In repo controller entry action, show the page for the file even if it's binary (so user still has access to history etc links). This makes it possible to use the entry action as the default when a file is clicked on

= AwesomeNestedSet

Awesome Nested Set is an implementation of the nested set pattern for ActiveRecord models. It is replacement for acts_as_nested_set and BetterNestedSet, but awesomer.

== What makes this so awesome?

This is a new implementation of nested set based off of BetterNestedSet that fixes some bugs, removes tons of duplication, adds a few useful methods, and adds STI support.

== Installation

If you are on Rails 2.1 or later:

  script/plugin install git://github.com/collectiveidea/awesome_nested_set.git
  
== Usage

To make use of awesome_nested_set, your model needs to have 3 fields: lft, rgt, and parent_id:

  class CreateCategories < ActiveRecord::Migration
    def self.up
      create_table :categories do |t|
        t.string :name
        t.integer :parent_id
        t.integer :lft
        t.integer :rgt
      end
    end

    def self.down
      drop_table :categories
    end
  end

Enable the nested set functionality by declaring acts_as_nested_set on your model

  class Category < ActiveRecord::Base
    acts_as_nested_set
  end
  
Run `rake rdoc` to generate the API docs and see CollectiveIdea::Acts::NestedSet::SingletonMethods for more info.

== View Helper

The view helper is called #nested_set_options. 

Example usage:

  <%= f.select :parent_id, nested_set_options(Category, @category) {|i| "#{'-' * i.level} #{i.name}" } %>

  <%= select_tag 'parent_id', options_for_select(nested_set_options(Category) {|i| "#{'-' * i.level} #{i.name}" } ) %>

See CollectiveIdea::Acts::NestedSet::Helper for more information about the helpers.

== References

You can learn more about nested sets at:

  http://www.dbmsmag.com/9603d06.html
  http://threebit.net/tutorials/nestedset/tutorial1.html
  http://api.rubyonrails.com/classes/ActiveRecord/Acts/NestedSet/ClassMethods.html
  http://opensource.symetrie.com/trac/better_nested_set/


Copyright (c) 2008 Collective Idea, released under the MIT license