code: protected ListView<T> newRadioListView(final String id,
  		final IModel<RadioGroupModelBean<T>> model)
  	{
  		final ListView<T> radioListView = new ListView<T>("choice", model.getObject().getRadios())
  		{
  			/**
  			 * The serialVersionUID.
  			 */
  			private static final long serialVersionUID = 1L;
  
  			/**
  			 * {@inheritDoc}
  			 */
  			@Override
  			protected void populateItem(final ListItem<T> item)
  			{
  				final Radio<T> radio = new Radio<>("radio", item.getModel(),
  					RadioGroupPanel.this.group);
  				radio.setOutputMarkupId(true);
  				item.add(radio);
  				item.add(
  					RadioGroupPanel.this.newLabel("label", radio.getMarkupId(), item.getModel()));
  			}
  		};
  		radioListView.setOutputMarkupId(true);
  		return radioListView;
  	}
docs: Factory method for create the new {@link ListView} for the {@link Radio} objects. This method
  is invoked in the constructor from the derived classes and can be overridden so users can
  provide their own version of a new {@link ListView} for the {@link Radio} objects.
  
  @param id
  the id
  @param model
  the model
  @return the new {@link ListView} for the {@link Radio} objects.