code: CmsContainerElementBean getElementForEditHandler(DialogContext context) {
  
          List<Item> selected = context.getSelectedItems();
          if (selected.size() == 1) {
              Item item = selected.get(0);
              Date instanceDate = (Date)item.getItemProperty(INSTANCEDATE_PROPERTY).getValue();
              CmsResource resource = context.getResources().get(0);
              return new CmsContainerElementBean(
                  resource.getStructureId(),
                  null,
                  Collections.singletonMap(
                      CmsDateSeriesEditHandler.PARAM_INSTANCEDATE,
                      String.valueOf(instanceDate.getTime())),
                  false);
          }
          return null;
      }
docs: Creates an element bean of the selected table item to be used with edit handlers.<p>
  
  @param context the dialog context
  
  @return the element bean