I have noticed on Polish discussion forums devoted to Delphi programming (such as news://pl.comp.lang.delphi and news://pl.comp.lang.delphi.bazy-danych) there are often questions about changing colors in DBGrid. It is a very easy task and I would like to offer some clues here.

The first step is to turn off the DefaultDrawing property of DBGrid by setting its value to False.

Let's consider the following example:

• We have a dataset which is using CachedUpdates.
• The user wants to know which records were edited, which are new, and which were deleted.

Such information about CachedUpdates can be accessed with the UpdateStatus function. To display records deleted from the dataset (before applying updates) we will modify the UpdateRecordTypes property. This property specifies which records should be visible in a dataset -- by default it is equal to [rtModified, rtInserted, rtUnmodified]. So in our code we must add a following line:

UpdateRecordTypes := UpdateRecordTypes + [rtDeleted];

Now let's go to DBGrid and add a handler for the OnDrawColumnCell event as follows:

procedure TForm1.DBGrid1DrawColumnCell(Sender: TObject; const Rect: TRect;
  DataCol: Integer; Column: TColumn; State: TGridDrawState);
begin
  with (Sender as TDBGrid).Canvas do begin
    case (DataSource.DataSet as TBDEDataSet).UpdateStatus of
      usInserted : Brush.Color := clRed;
      usModified : Brush.Color := clBlue;
      usDeleted  : begin Brush.Color := clBlack; Font.Color := clWhite; end;
    end;
    DefaultDrawColumnCell(Rect, DataCol, Column, State);
  end;
end;

DefaultDrawDataCell will now draw text using new font and brush properties. Easy, isn't it?