I'm trying to update nested question_output attributes in a 'question' model. A question has_one question_output. If there are no existing question_outputs in the database, everything works fine. But if the record already has a question_output, I get the following when trying to update:
Failed to remove the existing associated question_output. The record failed to save when after its foreign key was set to nil.
I would have thought the allow_destroy would take care of that, but alas - no joy. Admittedly I haven't used has_one much before. But if anyone has any ideas on how to fix this, I'd be appreciative. Relevant code below:
The form:
= form_for [@question.project, @question], :as => :question, :url => admin_project_question_path(@question.project, @question) do |f|
= render '/shared/form_errors', :model => @question
= f.fields_for :question_output_attributes do |qo|
.field
= qo.label :question_type
= qo.select :question_type, QuestionOutput::QUESTION_TYPES
.field
= qo.label :client_format
= qo.select :client_format, QuestionOutput::CLIENT_FORMATS
.field
= qo.label :required
= qo.check_box :required
.field
= qo.label :min_input, 'Length'
= qo.text_field :min_length
= qo.text_field :max_length
= f.submit 'Save Question Formatting'
Question model:
class Question < ActiveRecord::Base
has_one :question_output
accepts_nested_attributes_for :question_output, :allow_destroy => true
end
QuestionOutput model:
class QuestionOutput < ActiveRecord::Base
belongs_to :question
end
Questions controller:
class Admin::QuestionsController < ApplicationController
def show
@question = Question.find(params[:id])
@question.question_output ||= @question.build_question_output
end
def update
@question = Question.find(params[:id])
if @question.update_attributes(params[:question])
flash[:notice] = t('models.update.success', :model => "Question")
redirect_to admin_project_question_path(@question.project, @question)
else
flash[:alert] = t('models.update.failure', :model => "Question")
redirect_to admin_project_question_path(@question.project, @question)
end
end
end
In your question model change the has_one line to:
has_one :question_output, :dependent => :destroy
the :allow_destroy => true
on the accepts_nested_attributes
allows you to delete a question_output from within the question form via the _destroy=1
HTML attribute.
The :dependent => :destroy
deletes the question_output when you delete the question. Or in your case deletes the question_output when it is replaced by a new one.