Example5: DOM Events

<div id="the_div">
  <ul id="the_list">
    <li id="the_item">Click me!</li>
  </ul>
</div>

<p id="log"></p>

<script type="text/javascript" charset="utf-8">
  function log(string){
    document.getElementById('log').innerHTML += (string + '<br/>');
  }

  document.getElementById('the_div').addEventListener(
    'click', function(){ log('the_div!') }, true);
    
  document.getElementById('the_list').addEventListener(
    'click', function(){ log('the_list!') }, true);
    
  document.getElementById('the_item').addEventListener(
    'click', function(){ log('the_item!'); }, true);
</script>

<!--
   1. Change the addEventListener calls so that the events occur in the following order.      
      the_div! the_item! the_list!
      
      document.getElementById('the_list').addEventListener(
        'click', function(){ log('the_list!') }, false);
      
      observe the_list in bubbling mode (while got back shallow after going deep down)
      
   2. Change the addEventListener calls so that the events occur in the following order.      
      the_item! the_list! the_div!
      
      document.getElementById('the_div').addEventListener(
        'click', function(){ log('the_div!') }, false);

      document.getElementById('the_list').addEventListener(
        'click', function(){ log('the_list!') }, false);

      document.getElementById('the_item').addEventListener(
        'click', function(){ log('the_item!') }, false);
      
      observe all in bubbling mode. (Goes for deep to shallow)
      
   3. Change the addEventListener calls so that the events occur in the following order.      
      the_item! (no other events)
      
      document.getElementById('the_item').addEventListener(
        'click', function(event){ log('the_item!'), event.stopPropagation(); }, false);
      
      Add a stop propagation to the_list. That will prevent bubbling back up
-->