Components for Delphi and C++ Builder.

procedure TForm1.DBGridEh1CellMouseClick(Grid: TCustomGridEh; Cell: TGridCoord;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer;
  var Processed: Boolean);
var
  Center: TPoint;
  GridCrack: TCustomGridEhCrack;
  ACellRect: TRect;
begin
  if (Cell.X = 6) and not (ssDouble in Shift) then
  begin
    GridCrack := TCustomGridEhCrack(Grid);
    ACellRect := GridCrack.CellRect(Cell.X, Cell.Y);
    if (Abs(ACellRect.Width div 2 - X) < 8) and
       (Abs(ACellRect.Height div 2 - Y) < 8)
    then
    begin
      MemTableEh1.Edit;
      MemTableEh1.FieldByName('BoolField').AsBoolean :=
        not MemTableEh1.FieldByName('BoolField').AsBoolean;
      MemTableEh1.Post;
    end;
    Processed := True;
  end;
end;

function TMyDBGridEh.CanCharShowEditor(Ch: Char): Boolean;
begin
  Result := False;
end;