acts as list -- adding or moving new item to new location

rubyonrails-talk
1

right now i'm adding an item to my 'list' but i'm unsure how to move it to a certain spot in the list. specifically i want to put it at the bottom of the list. i assumed that if i did something like

parent.children << new_child

then the 'position' field in the child table would be given some sensible default by rails but instead it's set to NULL.

of course there's a bunch of ugly ways i can make this work but i'm wondering what would be the best/cleanest way...?

thanks in advance, mike

2

You must be doing something wrong if position is not being set by acts_as_list.

Here's an example:

---- migrations create_table :parents, :force => true do |t| end

create_table :children, :force => true do |t|   t.column :parent_id, :integer   t.column :name, :string   t.column :position, :integer end

---- models class Parent < ActiveRecord::Base   has_many :children, :order => :position end

class Child < ActiveRecord::Base   belongs_to :parent   acts_as_list :scope => parent end

---- some methods on acts_as_list you can use to manipulate the list decrement_position first? higher_item in_list? increment_position insert_at last? lower_item move_higher move_lower move_to_bottom move_to_top remove_from_list

---- so you can do stuff like puts parent.children[0].first? #=> true parent.children[0].move_lower parent.children[2].move_to_top