How can you validate the presence of a belongs to association with Rails?

Question

Say I have a basic Rails app with a basic one-to-many relationship where each comment belongs to an article:

$ rails blog
$ cd blog
$ script/generate model a         


        

Answer 1

I fixed this problem adding this follow line to my _comment.html.erb:

"NEW" if form.object.new_record? %>

Now, the validation works in stand alone form, and in multi form too.