code: public void initializeWidgets(CmsPopup dialog) {
  
          // creates tabs, etc. if necessary
          setupFieldContainer();
          addSpecialFields();
          // create fields and add them to the correct location
          buildFields();
          m_form.setValidatorClass("org.opencms.gwt.CmsDefaultFormValidator");
          m_form.render();
          if ((dialog != null) && (dialog.getWidth() > 20)) {
              getForm().getWidget().truncate("property_editing", dialog.getWidth() - 20);
          }
      }
docs: Initializes the widgets for editing the properties.<p>
  
  @param dialog the dialog which the property editor is part of