code: public void setValueEntity(I_CmsEntityRenderer renderer, CmsEntity value) {
  
          if (m_hasValue) {
              throw new RuntimeException("Value has already been set");
          }
          m_hasValue = true;
          m_isSimpleValue = false;
          FlowPanel entityPanel = new FlowPanel();
          m_widgetHolder.add(entityPanel);
          int index = getValueIndex();
          m_handler.ensureHandlers(index);
          renderer.renderForm(value, entityPanel, m_handler, index);
          removeStyleName(formCss().emptyValue());
      }
docs: Sets the value entity.<p>
  
  @param renderer the entity renderer
  @param value the value entity