Question

I have a Content model which has one or many Audio files which need to be added by the new/edit form.
What I have did is created the models with this relationship:

class Audio < ActiveRecord::Base
  belongs_to :content
  has_attached_file :audiofile,
end

class Content < ActiveRecord::Base
  ...
  has_many :audios
  accepts_nested_attributes_for :audios, :allow_destroy => true
end

Now in my new Content form I have the following:

<% f.fields_for :audios do |audiof| -%>

  <%= f.label :audiofile, 'Audio file:' %>&nbsp;
  <%= audiof.file_field :audiofile %>

<% end -%>

What I need it to do is show me the file_field only for a new Audio file and for the existing ones just print me a file size,name and probably a delete button.

I have also created a new record in the controller with:

@content.audios.build

I am using Rails 3.0.3 with Paperclip plugin for upload. Sorry if the question is too nooby.

Thanks.

Answer 1

From my memory, you will be able to access to the instance of the object within the fields_for statement.

Try something like that :

<% f.fields_for :audios do |audiof| -%>
  <% if audiof.object.new_record? %>
    <%= f.label :audiofile, 'Audio file:' %>&nbsp;
    <%= audiof.file_field :audiofile %>
  <% else %>
    <%= "Filename = #{audiof.object.audiofile.filename}" %>
    <%= "url = #{audiof.object.audiofile.url}" %>
  <% end %>
<% end -%>

If audiof.object returns nil(In that case, it is not the good name), check by displaying all the public methods <% = raise audiof.public_methods.inspect %>

The object method should return an instance of an Audio class.