How to include "Timer control" for Quiz App

Question

I'm a newbie to Rails and I'm developing a sample application for Online Quiz.

I've developed the application successfully. Now I would like to add Timing Constraint for my application.

But, I don't know how to add timer to the questions. I browsed various blogs and I couldn't find the appropriate answer.

But I found many coding in AJAX and JavaScript for the timer.

Let me know that we can or can't able to write timer control in Ruby on rails?

I would like to get your guidence to complete my first application.

Answer 1

I had mad quiz application. My apps have a model to store timing of quiz, example :

Quiz table attribute :
- time -> integer

Timer Table attribute :
- start_quiz -> Datetime
- end_quiz -> Datetime
- end_timing_quiz -> Datetime
- finished -> boolean
- user_id -> integer
- quiz_id -> integer

Illustration:

Admin make a quiz and put time to quiz (in minutes).

When user will get quiz, calculation of time with DateTime.now and then save to end_timing_quiz

def start_quiz
 @quiz = Quiz.find(params[:id]
 # check if user started of quiz.
 if Timer.where(:quiz_id => @quiz.id, :user_id => current_user.id).empty?
   @now = DateTime.now
   @end = @now + @quiz.time.minutes
   @time = Timer.create(:quiz_id => @quiz.id, :user_id => current_user.id, :start_quiz => @now, :end_timing_quiz => @end, :finished => false)
 else
   @time = Time.where(:quiz_id => @quiz.id, :user_id => current_user.id).first
 end
end

And on view you can using jQuery Countdown, and get end of time from @time

<%= javascript_include_tag "countdown" %>

<div class="countdown"></div>

<script type="text/javascript">

    $(document).ready(function() {
        var date = new Date('<%= @time.end_timing_quiz %>'.replace(/\-/g,'\/').replace(/[T|Z]/g,' '));
        $('.countdown').countdown({
            until: date,
            format: 'dHMS'
        });
    });

</script>

So, even if user leaves the quiz or reload of browser before quiz expires, timer still countdown also user can't control of timer.