docs: public static void show(DateRange dateRange, IResponseCallback<DateRange> callback) {
          Map<String, Object> args = new HashMap<>();
          args.put("dateRange", dateRange);
          Window dlg = (Window) PageUtil.createPage(DialogConstants.RESOURCE_PREFIX + "dateRangeDialog.fsp", null, args)
                  .get(0);
          dlg.modal((event) -> {
              callback.onComplete((DateRange) dlg.getAttribute("result"));
          }