Updating extra attributes in a has_many, :through relationship using Rails
- by Robbie
I've managed to set up a many-to-many relationship between the following models
Characters
Skills
PlayerSkills
PlayerSkills, right now, has an attribute that Skills don't normally have: a level.
The models look something like this (edited for conciseness):
class PlayerSkill < ActiveRecord::Base
belongs_to :character
belongs_to :skill
end
class Skill < ActiveRecord::Base
has_many :player_skills
has_many :characters, :through => :player_skills
attr_accessible :name, :description
end
class Character < ActiveRecord::Base
belongs_to :user
has_many :player_skills
has_many :skills, :through => :player_skills
end
So nothing too fancy in the models...
The controller is also very basic at this point... it's pretty much a stock update action.
The form I'm looking to modify is characters#edit.
Right now it renders a series of checkboxes which add/remove skills from the characters.
This is great, but the whole point of using has_many :through was to track a "level" as well.
Here is what I have so far:
- form_for @character do |f|
= f.error_messages
%p
= f.label :name
%br
= f.text_field :name
%p
= f.label :race
%br
= f.text_field :race
%p
= f.label :char_class
%br
= f.text_field :char_class
%p
- @skills.each do |skill|
= check_box_tag "character[skill_ids][]", skill.id, @character.skills.include?(skill)
=h skill.name
%br
%p
= f.submit
After it renders "skill.name", I need it to print a text_field that updates player_skill.
The problem, of course, is that player_skill may or may not exist! (Depending on if the box was already ticked when you loaded the form!)
From everything I've read, has_many :through is great because it allows you to treat the relationship itself as an entity... but I'm completely at a loss as to how to handle the entity in this form.
As always, thanks in advance for any and all help you can give me!
