Rails 4: accepts_nested_attributes_for and mass assignment

Question

I am trying to reproduce railscast #196 in Rails 4. However, I\'m experiencing some problems.

In my example I try to generate a Phonebook - each Person could have mu

Answer 1

In order to get three phones in the view change form_for :person to form_for @person (you want to use the object you've built here) as follows:

<%= form_for @person, url: people_path do |f| %>

This should fix the ForbiddenAttributes error as well.

And your create action could be:

def create
    @person = Person.create(person_params)

    redirect_to people_path
end

Update:

<%= form_for :person do |f| %> creates a generic form for the Person model and is not aware of the additional details you apply to a specific object (in this case @person in your new action). You've attached three phones to the @person object, and @person is not the same as :person which is why you didn't see three phone fields in your view. Please reference: http://apidock.com/rails/ActionView/Helpers/FormHelper/form_for for further details.