Question

I have a model Post which belongs_to one Section. There are two different Section subclasses and I use STI to implement different behavior for each of them. In the Post form I would like to have a tab for each Section. The tab will let the user either A) Pick from an existing Section using a <select> or B) Let the user create a new Section. I would like to know how to use accepts_nested_attributes_for and fields_for or whatever is required to get this done The Rails Way.

Any advice is greatly appreciated. Thanks.

Answer 1

Assuming the tabs correspond to the two subclasses

class Post
  # the two subclasses. Each instance will only be using one or the other
  belongs_to :section_foo
  belongs_to :section_bar

  accepts_nested_attributes_for :section_foo
  accepts_nested_attributes_for :section_bar
end

And in the view (probably once per tab)

= form_for @post do |f|
  = f.select :section_id, SectionFoo.all # etc
  = fields_for @post.build_section_foo do |s|
    = s.text_field :bla_bla_bla

That should get you 85% of the way there. You might need some :reject_if bidness on the accepts_* to avoid creating a new section and assigning an old section.