code: protected CheckBox newCheckBox(final String id, final IModel<M> model)
  	{
  		final IModel<Boolean> propertyModel = new PropertyModel<>(model.getObject(), this.getId());
  		return ComponentFactory.newCheckBox(id, propertyModel);
  	}
docs: Factory method for create a new {@link CheckBox}. This method is invoked in the constructor
  from this class and can be overridden so users can provide their own version of a new
  {@link CheckBox}.
  
  @param id
  the id
  @param model
  the model
  @return the new {@link CheckBox}.