title: Extending Backbone Views
body: <p>I have searched a lot but haven't been able to find a suitable answer.
  I'm trying to override a function defined in a Marionette CompositeView. I extended the composite view with a new class with function that should overwrite the default, everything works as expected, but problem is that the parent/original class(ClassA) still calls the old function instead of the new one(ClassB)</p>
  
  <pre><code>var ClassA = Backbone.Marionette.CompositeView.extend({
      initialize: function(){
          this.onValueAdded();
          // now the onValueAdded of ClassB should be called, or at least this is what im trying to accomplish
      },
      onValueAdded: function () {
  
      }
  });
  
  var ClassB = ClassA.extend({
      onValueAdded: function () {
          alert('this should get fired');
      }
  });
  </code></pre>