draw cell in TIB_Grid

{
var
  gr_RezCli: TIB_Grid;

gr_RezCli.OnDrawCell := gr_RezCliDrawCell;
}

// draw icon in cell if field REZ_MEMO is not empty
procedure TW_Rez.gr_RezCliDrawCell( Sender: TObject; ACol, ARow: Integer;
                                    Rect: TRect; State: TGridDrawState );
var
  sFieldName : String;
  bmp        : TBitmap;
  iLeftMargin: Integer;
  iTopMargin : Integer;
  DrawRect   : TRect;
begin
  if (gdFixed in State) or
     not Assigned(gr_RezCli) or
     not Assigned(gr_RezCli.GridFields[ACol-1]) or
     not Assigned(W_DM_Rez) or
     not Assigned(W_DM_Rez.D_Rez_Cli) or
     not Assigned(W_DM_Rez.Q_Rez_Cli) or
     //not W_DM_Rez.Q_Rez_Cli.Prepared or
     not W_DM_Rez.Q_Rez_Cli.Active or
     W_DM_Rez.Q_Rez_Cli.FieldByName('ID_REZEPT').IsNull or
     (W_DM_Rez.Q_Rez_Cli.RecordCount < 1) then
  begin
    exit;
  end;

  try
    W_DM_Rez.Q_Rez_Cli.BufferRowNum := gr_RezCli.DataRow[ARow];
    sFieldName := UpperCase( gr_RezCli.GridFields[ACol-1].FieldName );

    if (sFieldName = 'REZ_MEMO') and
       not W_DM_Rez.Q_Rez_Cli.BufferFieldByName('REZ_MEMO').IsNull then
    begin
      // inflate rect by line width
      Rect.Left   := Rect.Left + 1;
      Rect.Right  := Rect.Right - 1;
      Rect.Top    := Rect.Top + 1;
      Rect.Bottom := Rect.Bottom - 1;
      // fill background
      gr_RezCli.Canvas.FillRect( Rect );
      // icon
      bmp := TBitmap.Create;
      try
        // load bitmap from resource
        Bingo_LoadBitmapByIdent( imgDateInfo, bmp );
        // center icon
        iLeftMargin := ((Rect.Right-Rect.Left) - bmp.Width) div 2;
        iTopMargin  := ((Rect.Bottom-Rect.Top) - bmp.Height) div 2;
        DrawRect := Bounds( Rect.Left+iLeftMargin, Rect.Top+iTopMargin, bmp.Width, bmp.Height );
        // draw icon
        gr_RezCli.Canvas.BrushCopy( DrawRect, bmp, Bounds(0, 0, bmp.Width, bmp.Height),
                                    bmp.TransparentColor );
      finally
        bmp.Free;
      end;
    end;
  except
    on E: Exception do begin
      // log stuff
    end;
  end;
end;