application.js

$(document).ready(function () {
  $('form').submit(function(event){
    event.preventDefault();
    var action = $(this).attr("action");
    var roll = Math.floor(Math.random()*6 + 1);
    alert(roll);
    $.post(action, { "value" : roll }, function(response){
      $('#die').html(response)
    });
    
  });

  // PSEUDO-CODE:
  //   1- intercept the form submission event using jQuery
  //   2- prevent the default action for that event from happening
  //   3- generate a random number between 1 and 6 using JavaScript
  //   4- use jQuery to submit an AJAX post to the form's action
  //   5- when the AJAX post is done, replace the contents of the "#die" DIV in the DOM using jQuery

});

// var roll = $(this).attr('value');
//   $.post(value, )  

index.erb

<div class="container">
  <h1>Simplest Possible AJAX</h1>
  <p>This contrived app will simulate a roll of a 6-sided die.</p>

  <form method="post" action="/rolls">
    <input type="submit" value="Roll the Die">
  </form>

  <div id="die">

  </div>

</div>

<!-- 
# TODO: convert this route to use AJAX
post '/rolls' do
  # If the user passes-in a "value", let's use it. Otherwise, we'll generate a random one.
  # See: roll_if_value_is_nil method in the Roll model.
  value = params[:value] ? params[:value].to_i : nil

  @roll = value ? Roll.create({ value: value }) : Roll.create

  erb :index  # HINT: what does this do? what should we do instead?
end -->

lucky_ajax.md

Instructions:

1. Download this application skeleton.
2. Convert the app to use AJAX.
3. Add any files you changed to your gist and submit your code.

roll.erb

<img src="/<%= @roll.value %>.png" title="<%= @roll.value %>" alt="the roll">