Marking multi-level nested forms as "dirty" in Rails
- by Charles Kihe
I have a three-level multi-nested form in Rails. The setup is like this: Projects have many Milestones, and Milestones have many Notes. The goal is to have everything editable within the page with JavaScript, where we can add multiple new Milestones to a Project within the page, and add new Notes to new and existing Milestones.
Everything works as expected, except that when I add new notes to an existing Milestone (new Milestones work fine when adding notes to them), the new notes won't save unless I edit any of the fields that actually belong to the Milestone to mark the form "dirty"/edited.
Is there a way to flag the Milestone so that the new Notes that have been added will save?
Edit: sorry, it's hard to paste in all of the code because there's so many parts, but here goes:
Models
class Project < ActiveRecord::Base
has_many :notes, :dependent => :destroy
has_many :milestones, :dependent => :destroy
accepts_nested_attributes_for :milestones, :allow_destroy => true
accepts_nested_attributes_for :notes, :allow_destroy => true, :reject_if => proc { |attributes| attributes['content'].blank? }
end
class Milestone < ActiveRecord::Base
belongs_to :project
has_many :notes, :dependent => :destroy
accepts_nested_attributes_for :notes, :allow_destroy => true, :allow_destroy => true, :reject_if => proc { |attributes| attributes['content'].blank? }
end
class Note < ActiveRecord::Base
belongs_to :milestone
belongs_to :project
scope :newest, lambda { |*args| order('created_at DESC').limit(*args.first || 3) }
end
I'm using an jQuery-based, unobtrusive version of Ryan Bates' combo helper/JS code to get this done.
Application Helper
def add_fields_for_association(f, association, partial)
new_object = f.object.class.reflect_on_association(association).klass.new
fields = f.fields_for(association, new_object, :child_index => "new_#{association}") do |builder|
render(partial, :f => builder)
end
end
I render the form for the association in a hidden div, and then use the following JavaScript to find it and add it as needed.
JavaScript
function addFields(link, association, content, func) {
var newID = new Date().getTime();
var regexp = new RegExp("new_" + association, "g");
var form = content.replace(regexp, newID);
var link = $(link).parent().next().before(form).prev();
if (func) {
func.call();
}
return link;
}
I'm guessing the only other relevant piece of code that I can think of would be the create method in the NotesController:
def create
respond_with(@note = @owner.notes.create(params[:note])) do |format|
format.js { render :json => @owner.notes.newest(3).all.to_json }
format.html { redirect_to((@milestone ? [@project, @milestone, @note] : [@project, @note]), :notice => 'Note was successfully created.') }
end
end
The @owner ivar is created in the following before filter:
def load_milestone
@milestone = @project.milestones.find(params[:milestone_id]) if params[:milestone_id]
end
def determine_owner
@owner = load_milestone
@owner ||= @project
end
Thing is, all this seems to work fine, except when I'm adding new notes to existing milestones. The milestone has to be "touched" in order for new notes to save, or else Rails won't pay attention.
