[Rails] Add an index to a form

I haven't followed that particular tutorial, but I have used the Railscasts (73 - 75) and Ryan Bates' fabulous nested_form gem. Note that the 'casts show how to do it long-hand, and the gem simply wraps up all that work and puts a bow on it. You can probably simply follow the directions from the gem and get on with your life if you already know the theory.

Walter

You should not have a space between semantic_fields_for and (. That
is ruby syntax. Whether it fixes you problem is another matter.

Colin

Thanks for your reply,

I've seen that cast, but when I add another form for another children the
HTML shows this

<input id="user_children_attributes_0_name" maxlength="255"
name="user[children_attributes][0][name]" type="text">

so it's not increasing and it will only save the first child

and now I'm trying what the cast says

_children.html.erb

<%= f.semantic_fields_for "user[children][]", user do |children| %>
.....
<% end %>

and I get this

undefined local variable or method `user'


It's maybe something I'm not seeing, I'm starting with rails and I hope
someone can help me

Thanks

In the casts I've seen this

<div id="tasks">
<%= render :partial => 'task', :collection => @project.tasks %>
</div>

so as far as I understand theres a file _task.html.erb, but they
create tasks by building it in the controller
should I do something like that?, I mean
<%= render "children", :collection => @user.childrens %>

Here's an extraction from a site that's using Ryan's plug-in (a person can have N images):

#people_controller.rb
...
def new
@person = Person.new
@person.images.build
end
...

#person.rb
class Person < ActiveRecord::Base
attr_accessible :images_attributes, :name, :sort_name, :birth, :death, :nationality, :historical_period, :short_description, :bio
has_many :images, :as => :attachable, :dependent => :destroy
accepts_nested_attributes_for :images, :reject_if => lambda { |a| a[:file].blank? && a[:file_uid].blank? && a[:file_url].blank? && a[:name].blank? }, :allow_destroy => true
validates :name, :presence => true
validates :nationality, :presence => true
validates :historical_period, :presence => true
end

#image.rb
class Image < ActiveRecord::Base
attr_accessible :name, :attachable_type, :attachable_id, :file_name, :file_url, :file_uid, :file, :retained_file, :remove_file, :created_at, :file_height, :updated_at, :file_width
image_accessor :file
belongs_to :attachable, :polymorphic => true
def label
name.blank? ? file_name : name
end
end

#people/_form.html.erb
<%= nested_form_for @person, :url => person_path(@person, :page => params[:page]), :html => {:multipart => true} do |f| %>
<%= f.error_messages %>

...

<div id="images" class="tabbed">
<%= f.fields_for :images %>
<p class="clear-both">
<%= f.link_to_add "Add an image", :images %>
</p>
</div>
<p><%= f.submit %></p>
<% end %>

#people/_image_fields.html.erb (this name is critical to success)
<p class="clear-both image">
<%- if f.object.file_uid -%>
<span class="left">
<%= link_to( image_tag( f.object.file.thumb('60x60#').url, :class => 'border', :size => '60x60' ), f.object.file.url, :target => '_blank') %><br /><span class="hint"><%= f.object.file_width %> × <%= f.object.file_height %></span>
</span>
<%= f.link_to_remove "Delete", :class => 'delete' %>
<%- else -%>
<span class="left">
<%= image_tag( 'thumb_new.jpg', :class => 'border', :size => '60x60' ) %>
</span>
<%- end -%>
<%= f.label :name %>
<%= f.text_field :name %><br />
<%= f.label :file, "Upload" %>
<%= f.file_field :file %>
<%= f.hidden_field :retained_file %><br />
<%= f.label :file_url, "Upload From URL" %>
<%= f.text_field :file_url %>
</p>


That is quite literally all there is to it, except to follow the rest of the install directions on the Github page.

Walter

I think that the space after f.semantic_fields_for and the parentheses
around the argument list are interacting to produce the error.

I think that you can probably do either fix and resolve the issue:

<%= f.semantic_fields_for "user[children_attributes][]", user do |
fes| %>

<%= f.semantic_fields_for("user[children_attributes][]", user) do
-Rob

Rob Biedenharn
[email protected] http://AgileConsultingLLC.com/
[email protected] http://GaslightSoftware.com/