/** Retrieve item types and fill in the item types combo box. */
 private void init() {
   Response res = ClientUtils.getData("loadItemTypes", new GridParams());
   Domain d = new Domain("ITEM_TYPES");
   if (!res.isError()) {
     ItemTypeVO vo = null;
     list = ((VOListResponse) res).getRows();
     for (int i = 0; i < list.size(); i++) {
       vo = (ItemTypeVO) list.get(i);
       d.addDomainPair(vo.getProgressiveHie02ITM02(), vo.getDescriptionSYS10());
     }
   }
   controlHierarchy.setDomain(d);
   controlHierarchy
       .getComboBox()
       .addItemListener(
           new ItemListener() {
             public void itemStateChanged(ItemEvent e) {
               if (e.getStateChange() == e.SELECTED) {
                 ItemTypeVO typeVO = (ItemTypeVO) list.get(controlHierarchy.getSelectedIndex());
                 treePanel.setCompanyCode(typeVO.getCompanyCodeSys01ITM02());
                 treePanel.setProgressiveHIE02((BigDecimal) controlHierarchy.getValue());
                 DetailSupplierVO vo =
                     (DetailSupplierVO) supplierPanel.getVOModel().getValueObject();
                 treePanel.setCompanyCode(vo.getCompanyCodeSys01REG04());
                 treePanel.reloadTree();
                 itemsGrid.clearData();
               }
             }
           });
   if (d.getDomainPairList().length == 1) controlHierarchy.getComboBox().setSelectedIndex(0);
   else controlHierarchy.getComboBox().setSelectedIndex(-1);
 }