Fórum Tab Key #208083

procedure TForm1.MudarComEnter(var Msg: TMsg; var Handled: Boolean);
begin
  if not ((Screen.ActiveControl is TCustomMemo) or
          (Screen.ActiveControl is TCustomGrid) or
          (Screen.ActiveForm.ClassName = ´TMessageForm´)) then
  begin
    if Msg.message = WM_KEYDOWN then
    begin
      Case Msg.wParam of
        VK_RETURN,VK_DOWN : Screen.ActiveForm.Perform(WM_NextDlgCtl, 0, 0);
        VK_UP : Screen.ActiveForm.Perform(WM_NextDlgCtl, 1, 0);
      end;
    end;
  end;
end;

  Application.OnMessage := MudarComEnter;