Rails, Simple Form, Nested Forms - ruby-on-rails

Question

class Project
has_many :project_questions, dependent: :destroy#, through: :projects
accepts_nested_attributes_for :project_questions
end
I am trying to make an app with rails 4 and Simple Form.
I have models called projects, project_questions and project_answers.
The associations between them are:
Projects:
has_many :project_questions, dependent: :destroy#, through: :projects
accepts_nested_attributes_for :project_questions
Project questions:
belongs_to :project#, counter_cache: true
has_many :project_answers, dependent: :destroy
belongs_to :user
accepts_nested_attributes_for :project_answers
belongs_to :user
Project answers:
belongs_to :project_question#, counter_cache: true
belongs_to :user
User:
has_many :project_questions
has_many :project_answers
class ProjectQuestions
belongs_to :project#, counter_cache: true
has_many :project_answers, dependent: :destroy
belongs_to :user
accepts_nested_attributes_for :project_answers
end
ProjectAnswer:
belongs_to :project_question#, counter_cache: true
belongs_to :user
My objective is to have a partial on my projects show page which displays the questions and their answers relating to the project and to have a link to another form where you can ask a question or answer one. I am struggling.
In my controllers I have:
Projects:
def project_params
params.require(:project).permit(project_question_attributes: [:title, :content, :user_id, :project_id,project_answer_attributes: [:answer, :project_question_id]],
Project_question:
def new
#project_question = ProjectQuestion.new
#project_id = params[:project_id]
#project_question.project_answers[0] = ProjectAnswer.new
end
Project_answer:
def new
#project_answer = ProjectAnswer.new
end
def project_question_params
params[:project_question].permit(:id, :title, :content, :project_id, :user_id,project_answer_atttibutes: [:id, :answer, :project_question_id, :user_id])
end
Then in my views I have:
Project#show:
<% if current_user.id == #project.creator_id %>
<%= link_to 'Ask a question', new_project_project_question_path(:project_id => #project.id) %>
<% end %>
<%= render 'project_questions/pqps' %>
Project_question#pqps (a partial):
<div class="containerfluid">
<div class="row">
<div class="col-md-10 col-md-offset-1">
<div class="categorytitle">
<%= #project_question.try(:title) %>
</div>
<div class="generaltext">
<%= #project_question.try(:content) %>
</div>
<span class="editproject">
<% if current_user.id == #project.creator_id %>
<% end %>
</span>
</div>
</div>
</div>
My project_questions form partial is:
<div class="containerfluid">
<div class="row">
<div class="col-md-10 col-md-offset-1">
<% f.simple_fields_for :project_questions do |f| %>
<%= f.input :project_id, as: :hidden, input_html: {value: #project_question_id} %>
<%= f.input :title, label: 'Question:', :label_html => {:class => 'categorytitle'}, placeholder: 'Type your question here', :input_html => {:style => 'width: 100%', class: 'categorytitle'} %>
<%= f.input :content, label: 'Is there any context or other information?', :label_html => {:class => 'categorytitle'}, placeholder: 'Context might help to answer your question', :input_html => {:style => 'width: 100%', rows: 5, class: 'generalprojecttext'} %>
<%= f.button :submit %>
<% end %>
</div>
</div>
</div>
Project_answer#pa (a partial):
(not yet written - still trying to get the questions to work)
My routes are:
resources :projects do
resources :project_questions do
resources :project_answers
end
end
When I try this, I get an error in my project_questions form that says:undefined local variable or methodf' for #<#:0x000001013d8298>`
I can't see where it is talking about f outside the form block. I have tried adding another line to the form for simple_fields for project and then nesting the project questions form inside of it, but that doesn't change anything.
Can anyone see what I've done wrong?
Thank you

Answer 1

You should change this line <% f.simple_fields_for :project_questions do |f|
%> to this <%= simple_form_for :project_questions do |f| %> in order to make it work.

Answer 2

The plataformatec simple_form wiki has a pretty good instructional page on using nested forms.
(Just as a side note, I find that it's often easier to diagnose problems without using partials. Once everything is working, you can clean-up by refactoring into partials.)
I believe you need to pass a local variable to your partial, so it knows what the first "f" refers to.
<%= render 'project_questions/pqps', locals: {f: f} %>
(You also may choose to use a different local variable in the partial for project_questions, just so you're always clear what is being referenced in error messages.)