Ajouter des RadioButton dans un TListBox

procedure TForm1.ListBox1DrawItem(Control: TWinControl; Index: Integer;
Rect: TRect; State: TOwnerDrawState);
var
drawRect: TRect;
begin
with ListBox1.Canvas do
begin
FillRect(rect);

drawRect.Left := rect.Left + 1;
drawRect.Right := Rect.Left + 13;
drawRect.Bottom := Rect.Bottom;
drawRect.Top := Rect.Top;

if odSelected in State then
DrawFrameControl(Handle, drawRect, DFC_BUTTON, DFCS_BUTTONRADIO or DFCS_CHECKED)
else
DrawFrameControl(Handle, drawRect, DFC_BUTTON, DFCS_BUTTONRADIO);

TextOut(15, rect.Top + 3, ListBox1.Items[Index]);
end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
ListBox1.Style := lbOwnerDrawVariable;
ListBox1.ItemHeight := 20;

//drei Test Items erstellen
ListBox1.Items.Add('Item 1');
ListBox1.Items.Add('Item 2');
ListBox1.Items.Add('Item 3');
end;