RoR creating a form and passing back a hash - ruby-on-rails

Question

thanks in advance for looking at my issue. I'm new to programming and struggling with the concept of saving data to "foreign tables".
So this is a basic survey. I have a list of questions, that have answers belonging to it.
Here is my code that iterates through all the questions and answers:
<% #questions.each do |question| %>
<ul><%= question.questiondescription %></ul>
<% #answers = question.answers %>
<% #answers.each do |answer| %>
<li><%= answer.answerdescription %></li>
<% end %>
<% end %>
This works great. However I want all the answers to be radio buttons and store the selections in another table. I have another controller and table called "assessment_results". It looks like this:
User_Id, Assessment_Id, Question_ID, Answer_Id
I need to create a new record in this table for each question and answer. How would I go about doing this with having all the questions listed on one page?
So my thinking is I need a hash to push into that table for every question.
{[user_id:1, assessment_id:, question_id:1, answer_id:3]}

Answer 1

You could use the radio_button_tag and parse the results yourself.
Here is the breakdown
Looking at your assessment_results table I assume you have an Assessment controller based on the 'assessment_id' column.
Lets use that to present the questions.
Here is the assessments/new.html.erb
<h1>New assessment</h1>
<%= form_for(#assessment) do |f| %>
<% if #assessment.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#assessment.errors.count, "error") %> prohibited this assessment from being saved:</h2>
<ul>
<% #assessment.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<% #questions.each do |question| %>
<%= question.questiondescription %>
<ul>
<% #answers = question.answers %>
<% #answers.each do |answer| %>
<li><%= answer.answerdescription %><%= radio_button_tag("questions[#{question.id}]", answer.id) %></li>
<% end %>
</ul>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
So we have a standard assessment form that really just gives us the form structure and assessment button, we aren't going to actually use anything from it.
Best to build the view and then look at the source code in a browser.
The work is being done by the radio_button_tag, the first value "questions[#{question.id}]"
Will produce radio buttons with a name of "questions[1]" for the first group of questions and the value will be the answer id.
When rails sees a parameter like questions[1], it will put this into a hash called questions.
Here is the raw hash from the log when submitting the form with answers filled out:
Parameters: {"utf8"=>"✓", "authenticity_token"=>"lwqT5y+xUaYvt/GBObpN+BBO3F4YO8XaEGWcpS84lVw=", "questions"=>{"1"=>"2", "2"=>"8", "3"=>"13", "4"=>"18", "5"=>"23"}, "commit"=>"Create Assessment"}
The questions hash is:
"questions"=>{"1"=>"2", "2"=>"8", "3"=>"13", "4"=>"18", "5"=>"23"}
Now in the assessments controller, for the create method, I did the following:
def create
#assessment = Assessment.new(user_id: current_user.id)
respond_to do |format|
if #assessment.save
params[:questions].each do |question, answer|
AssessmentResult.create(user_id: current_user.id, assessment_id: #assessment.id,
question_id: question, answer_id: answer)
end
format.html { redirect_to #assessment, notice: 'Assessment was successfully created.' }
format.json { render :show, status: :created, location: #assessment }
else
format.html { render :new }
format.json { render json: #assessment.errors, status: :unprocessable_entity }
end
end
end
First we are creating an assessment that belongs to the user, I am assuming that you are using Devise or a similar system that uses the current_user for the current logged in user.
Next after saving with #assessment.save, this gives us our #assessment.id that the assessment results will belong to.
So the core work is happening here:
params[:questions].each do |question, answer|
AssessmentResult.create(user_id: current_user.id, assessment_id: #assessment.id
question_id: question, answer_id: answer)
end
end
params[:questions] - this is the params question hash that was submitted by the form.
params[:questions].each do |question, answer| - this takes the hash and for each, entry splits it into the key and value with |key, value|, in this case the key was the question id and the value was the chosen answer id.
Now we store the answer in the AssessmentResult model/table with the create command.
Say you now want to display the results of the assessment with: /assessments/1/show
def show
#assessment_results = AssessmentResult.where(assessment_id: #assessment.id)
end
Now you have the question and selected answer in the AssessmentResult
Make sure you set up your relations in the model:
app/models/assessment_result.rb
class AssessmentResult < ActiveRecord::Base
belongs_to :question
belongs_to :answer
end
Simple display of quesiton and selected answer, you will have to add the 'correct answer' code yourself.
app/views/assessments/show.html.erb
<% #assessment_results.each do |ar| %>
<%= ar.question.questiondescription %>: <%= ar.answer.answerdescription %>
<br />
<% end %>

Answer 2

Ok, when you have a nested models, here's what you can do
<%= form_for(#question) do |f| %>
<%= f.fields_for :answer do |ff| %>
<%= ff.label :image, 'Tag:' %>
<%= ff.checkbox :description, multiple: true, name: "answer[description]" %>
In your case, you have several answers belonging to some question, the principle is the same except you have to build specific ids for each answer, so I strongly suggest you these very helpful railscast
http://railscasts.com/episodes/197-nested-model-form-part-2
http://railscasts.com/episodes/75-complex-forms-part-3