anchor.diff:    FEdit.Text := aFilter.DisplayValue;
   end;
   
  -procedure TmLookupFilterConditionPanel.SetFilterValue(const aValue : Variant; const aDescription: String);
  +procedure TmBaseLookupFilterConditionPanel.SetFilterValue(const aValue : Variant; const aDescription: String);
   begin
     if VarIsNull(aValue) then
       Self.Clear
  
positive.code:   Result := VarIsNull(FCurrentValue);
  end;
  
  { TmLookupFilterConditionPanel }
  
  procedure TmLookupFilterConditionPanel.OnEditValueChanged(Sender: TObject);
  begin
  
  end;
  
  procedure TmLookupFilterConditionPanel.OnShowLookup(Sender: TObject);
  var
    lookupFrm: TmLookupFrm;// TmLookupWindow;
    keyFieldName : string;
    tmpVirtualFieldDefs : TmVirtualFieldDefs;
  begin
    if not Assigned(FDataProvider) then
      raise Exception.Create('[TmLookupFilterConditionPanel] Missing DataProvider.');
  
  //  if FValueFieldName = '' then
  //    raise Exception.Create('[TmLookupFilterConditionPanel] Missing ValueFieldName.');
  
    lookupFrm := TmLookupFrm.Create(Self);
    try
  
negative.code:   FDisplayLabelFieldNames := TStringList.Create;
  end;
  
  destructor TmBaseLookupFilterConditionPanel.Destroy;
  begin
    FLookupFieldNames.Free;
    FDisplayLabelFieldNames.Free;
    inherited Destroy;
  end;
  
  procedure TmBaseLookupFilterConditionPanel.SetFilterCaption(aValue: String);
  begin
    inherited SetFilterCaption(aValue);
    Self.ApplyFilterCaption(FLabel, aValue, false);
  end;
  
  procedure TmBaseLookupFilterConditionPanel.ExportToFilter(aFilter: TmFilter);
  begin
    inherited ExportToFilter(aFilter);
    aFilter.DisplayValue:= FEdit.Text;
  