externalForm.addParameter(DROPDOWNMENU_KEY_PREVIOUS_VALUE, value.toString());
externalForm.addParameter(getDropDownMenuUniqueKeyPreviousValue(id, shortKeyPath), value.toString());
  public PresentationObject getPresentationObject(    Object entity,    EntityPath path,    EntityBrowser browser,    IWContext iwc) {    Object value = getValue(entity,path,browser,iwc);      Integer id = (Integer) ((EntityRepresentation) entity).getPrimaryKey();    // show drop down menu without a submit button if the entity is new    boolean newEntity = id.intValue() < 0;    String shortKeyPath = path.getShortKey();    String uniqueKeyLink = getLinkUniqueKey(id, shortKeyPath);    // decide to show a link or a drop down menu    if (newEntity || iwc.isParameterSet(uniqueKeyLink)) {      // show drop down menu with submitButton      String uniqueKeyDropdownMenu = getDropdownMenuUniqueKey(id, shortKeyPath);      DropdownMenu dropdownMenu =         getDropdownMenu(          value,           uniqueKeyDropdownMenu,          entity,          path,          browser,          iwc);      // add old value as hidden value      externalForm.addParameter(DROPDOWNMENU_KEY_PREVIOUS_VALUE, value.toString());        Table table = (newEntity) ? new Table(1,1) : new Table(2,1);      table.add(dropdownMenu,1,1);      // add submit button      if (! newEntity) {            SubmitButton button = new SubmitButton("OK", getGeneralSubmitKey(), getUniqueKey(id, shortKeyPath).toString());        button.setAsImageButton(true);        table.add(button,2,1);      }      return table;          }     else {      // show link      return getLink(value, uniqueKeyLink, iwc);    }        }