code: private boolean addCell2FormRow(final FormElement _formElement,
                                      final PrintQuery _query,
                                      final Field _field)
          throws EFapsException
      {
          boolean ret = true;
          Attribute attr = null;
          if (_field.getAttribute() != null) {
              attr = _query.getAttribute4Attribute(_field.getAttribute());
          } else if (_field.getSelect() != null) {
              attr = _query.getAttribute4Select(_field.getSelect());
          }
  
          final Instance fieldInstance = evaluateFieldInstance(_query, _field);
          if (_field.isHiddenDisplay(getMode())) {
              if (_field.getAttribute() != null) {
                  _query.getAttribute(_field.getAttribute());
              } else if (_field.getSelect() != null) {
                  _query.getSelect(_field.getSelect());
              } else if (_field.getPhrase() != null) {
                  _query.getPhrase(_field.getName());
              }
              addHidden(evaluateUIProvider(_query, _field, fieldInstance, attr));
              ret = false;
          } else {
              // fieldset
              if (_field instanceof FieldSet) {
                  _formElement.addValue(evaluateFieldSet(_query, _field, fieldInstance));
              } else if (_field instanceof FieldCommand) {
                  final UICmdField cell = new UICmdField(this, (FieldCommand) _field, getInstance());
                  _formElement.addValue(cell);
              } else if (_field instanceof FieldPicker) {
                  final UIField cell = new UIField(this, getInstance().getKey(),
                                  UIValue.get(_field, attr, null).setClassObject(this).setInstance(getInstance())
                                      .setCallInstance(getInstance()));
                  final UIPicker picker = new UIPicker((FieldPicker) _field, cell);
                  cell.setPicker(picker);
                  _formElement.addValue(cell);
              } else {
                  _formElement.addValue(evaluateUIProvider(_query, _field, fieldInstance, attr));
              }
          }
          return ret;
      }
docs: Method to add a Cell to the given Row.
  
  @param _formElement the form element
  @param _query query containing the values
  @param _field field the cell belongs to
  @return true if the cell was actually added, else false
  @throws EFapsException on error