Help with many-to-many nested form

Rails
#1

I have a form used to create a ‘Style’. The style may have any number of
‘features’ which correspond to ‘Feature’ models in the features table. I
would like to add the appropriate entries to a relationship table
(‘stylefeatures’) whenever a Style is created. Here is a breakdown of my
models:

class Style < ActiveRecord::Base

has_many :stylefeatures

has_many :features, :through => :stylefeatures, :foreign_key =>
:feature_id

accepts_nested_attributes_for :stylefeatures
end

class Feature < ActiveRecord::Base

has_many :stylefeatures

has_many :styles, :through => :stylefeatures, :foreign_key =>
:style_id
end

class Stylefeature < ActiveRecord::Base

belongs_to :style

belongs_to :feature

accepts_nested_attributes_for :features
end

…and here is my controller for the ‘new’ action:

def new

@style = Style.new

@features = Feature.all

end

…and here is my form:

<%= simple_form_for @style, :html => { :class => ‘form-horizontal’ } do
|m| %>

<%= m.simple_fields_for :features do |p| %>

<%= p.input :name, :label => "Features", :collection => @features,

:input_html => { :multiple => true } %>

<% end %>

[…]
<% end %>

Right, so the list of features DOES load up into the multiple select box
within my form. So that’s sweet. However, when I go to submit I receive
the
error: No association found for name ‘features’. Has it been defined
yet?

I get the exact same error when adding @style.features.build to the
controller ‘new’ action.

This is what the params hash looks like. It carries the ID of the
feature
name selected.

“features”=>{“name”=>["",“7”]}

So my question is, how do I go about loading the features listed in the
features table for the nested form, and on form submission, handle the
selected features for addition to the stylefeatures relationship table.

Thanks very much

#2

On 20 May 2012 21:01, Abram [email protected] wrote:

end

accepts_nested_attributes_for :features

I don’t know whether this is part or all of the problem, but you can’t
have :features here as it is belongs_to, so it should be singular (if
you need it at all).

By the way please don’t post html, or at least not complex html, it
makes the reply quoting very messy as you can see.

Colin

#3

Colin, thanks for your response. I have moved a bit further on my
original
problem of updating the through table.

I now have in my controller:

def new
@style = Style.new
@style.stylefeatures.build
@features = Feature.all
end

def create
@style = Style.new(params[:style])
@style.stylefeatures.build
@style.save
end

…and in my style model
*
*
attr_accessible :stylefeatures_attributes
has_many :stylefeatures
has_many :features, :through => :stylefeatures, :foreign_key =>
:feature_id
accepts_nested_attributes_for :stylefeatures

… and in my stylefeature model

belongs_to :style
belongs_to :feature
accepts_nested_attributes_for :feature

… and in my feature model

attr_accessible :description, :fullname, :name
has_many :stylefeatures
has_many :styles, :through => :stylefeatures, :foreign_key =>
:style_id

… and in my create form

<%= m.simple_fields_for :stylefeatures do |p| %>
  <%= p.input :feature_id, :label => "Features", :collection =>

@features, :input_html => { :multiple => true } %>
<% end %>

Now when I save the new Style, the stylefeatures table is updated with
the
appropriate style_id, but with two useless entries. The first is an
array
with all of the feature ids which have been selected in the form. The
second is a blank entry with the appropriate style_id and nothing in the
feature_id column.

Do you have any clue of what I might be doing wrong, or how to spread
the
collected feature_id’s into the table as desired?

Thanks,
Abram

#4

https://github.com/vishalsingh/multiple_upload_photo check this may be
helpful for you