How to pass value attribute of an object was saved, to view to create new object has that same value

Question

I have a new form for create question and answers. This is my form:

<%= simple_form_for [@question_type, @question], url: path, defaults: { error: false } do |question_form| %>
  <%= render 'shared/error_messages', object: question_form.object %>

  <div class="question_fields well">
    <%= question_form.input :content, input_html: { rows: 4, class: 'span6' } %>
    <%= question_form.input :mark, input_html: { class: 'span1' } %>
    <%= question_form.association :topic %>
  </div>
  <%= question_form.simple_fields_for :answers do |answer_form| %>
    <%= render 'answer', f: answer_form %>
  <% end %>
  <%= question_form.button :submit, class: "new_resource" %>
<% end %>

The question have 3 fields: content, mark, topic.

This is my create action in question controller:

def create
  @question = Question.new(params[:question])
  @question.question_type_id = params[:question_type_id]
  @question.user_id = current_user.id

  if @question.save
    flash[:success] = "Successfully created question."
    redirect_to new_question_type_question_path
  else
    render 'new'
  end
end

My routes:

resources :question_types, only: [:index] do
  resources :questions
end

Now, i want after user submit to create question successful, it will show new form again, but the topic select will display the topic of question was just saved. How can i do that?

Answer 1

#1 Solution -

If I understood your question correctly you can pass question's topic_id to new action after question saved successfully.

redirect_to new_question_type_question_path(:topic_id => @question.topic_id )

then in new action of questions controller, add topic_id if params[:topic_id] present?

something like this,

def new
  ...
  ...
  @topic_id = params[:topic_id] if params[:topic_id].present?
end

then in new form, display your topic using this @topic_id instance variable. I don't know too much about simple_form_for, but you can do something like,

<%= question_form.association :topic, :selected => (@topic_id.present? ? @topic_id : '') %>

OR

#2 Solution

To display the topic of last question saved, you just need last question object in new action. You don't need to do above steps of #1 Solution

def new
  ...
  ...
  @topic_id = current_user.questions.order('created_at ASC').last.topic_id if current_user.questions.present?
end

In new form do same thing as given in #1 Solution,

<%= question_form.association :topic, :selected => (@topic_id.present? ? @topic_id : '')