Проблема потери фокуса для TEdit

1. Drop two TEdits onto a form.

2. In the OnExit Event of Edit1 add the following code:

Application.MessageBox( 'Title','...', mb_ok );

3. Run the application.

4. First select Edit1 then Edit2

5. The Message box is shown.

Click the OK button, and the Caret has dissapeared!

6. How to handle this:

 procedure TForm1.Edit1Exit(Sender: TObject);
 begin
  Application.MessageBox('qq','qq',mb_ok);
  if Assigned(ActiveControl) then
    PostMessage(ActiveControl.Handle,WM_SETFOCUS,0,0);
 end;

Взято с сайта: https://www.swissdelphicenter.ch