manageable_observers_example.js

var JSClassObserver = Class.create({
  findElements: function(class_name) {
    var self = this;
    $('.' + class_name).each(function(index, element) {
      if(element.js_attached == null) {
        element.js_attached = {};
      }
      if(element.js_attached[class_name] != true) {
        self.attachBehavior(element, index);
        element.js_attached[class_name] = true;
        $(element).removeClass(class_name);
      }
    });
  }
});


var LinkObserver = {};

LinkObserver.attachExternalLink = Class.create(JSClassObserver.prototype, {
  init: function() {
    this.findElements('js_external_link'); 
  },
  attachBehavior: function(element) {
    $(element).click(function(event) {
      new_window = window.open($(this).attr('href'));
      LinkObserver.opened_windows.push(new_window);
      event.preventDefault();
    });
  }
});

LinkObserver.attachAllObservers = function() {
  new LinkObserver.attachExternalLink();
}

// Example
/*
Before:
<a href="http://www.google.com" class="js_external_link">Click for new window</a>

After:
<a href="http://www.google.com">Click for new window</a>
<script type="text/javascript">
  alert($('a').js_attached.js_external_link);
</script>
*/