Colocando um componente combobox em um componente stringgrid

//Inclua no seu Form um componente ComboBox e um componente StringGrid.

type
TForm1 = class(TForm)
StringGrid1: TStringGrid;
ComboBox1: TComboBox;
procedure FormCreate(Sender: TObject);
procedure ComboBox1Change(Sender: TObject);
procedure ComboBox1Exit(Sender: TObject);
procedure StringGrid1SelectCell
(Sender: TObject; Col, Row: Integer;
var CanSelect: Boolean);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
// Evento OnCreate do Form
procedure TForm1.FormCreate(Sender: TObject);
begin
{ Ajusta a altura do ComboBox com a altura da linha do StringGrid}
StringGrid1.DefaultRowHeight := ComboBox1.Height;
{Esconde o ComboBox}
ComboBox1.Visible := False;
end;
// Evento OnChange do componente ComboBox
procedure TForm1.ComboBox1Change
(Sender: TObject);
begin
StringGrid1.Cells[StringGrid1.Col,StringGrid1.Row]
:= ComboBox1.Items[ComboBox1.ItemIndex];
ComboBox1.Visible := False;
StringGrid1.SetFocus;
end;
// Evento OnExit do componente ComboBox
procedure TForm1.ComboBox1Exit
(Sender: TObject);
begin
StringGrid1.Cells[StringGrid1.Col,StringGrid1.Row]
:= ComboBox1.Items[ComboBox1.ItemIndex];
ComboBox1.Visible := False;
StringGrid1.SetFocus;
end;
// Evento OnSelectCell do componente StringGrid
procedure TForm1.StringGrid1SelectCell(Sender: TObject; Col, Row: Integer;
var CanSelect: Boolean);
var
R: TRect;
begin
if ((Col = 3) AND
(Row <> 0)) then begin
R := StringGrid1.CellRect(Col, Row);
R.Left := R.Left + StringGrid1.Left;
R.Right := R.Right + StringGrid1.Left;
R.Top := R.Top + StringGrid1.Top;
R.Bottom := R.Bottom + StringGrid1.Top;
ComboBox1.Left := R.Left + 1;
ComboBox1.Top := R.Top + 1;
ComboBox1.Width := (R.Right + 1) - R.Left;
ComboBox1.Height := (R.Bottom + 1) - R.Top;
ComboBox1.Visible := True;
ComboBox1.SetFocus;
end;
CanSelect := True;

end;