InputBox and other sub-forms don't close

[Iede]

I have a program in which I'm using inputboxes. When the inputbox opens, I'm able to key in a value, but after clicking Ok or Cancel the inputbox doesn't close and the program doesn't react to anything anymore: it has to be killed from the task list. Part of the code is:

var rstr: String;
begin
  rstr:= InputBox('Simulation', 'Reference-car', IntToStr(ReferenceCar));
  try
    ReferenceCar := StrToInt(rstr);
    if (ReferenceCar < 1) or (ReferenceCar > nVehicles) then
      ReferenceCar := 1;
    MyIniFile.WriteInteger('Settings', 'ReferenceCar', ReferenceCar)
  except
    on E: EConvertError do
      ShowMessage(E.ClassName + CRLF + E.Message)
  end
end;

The same happens also for other forms which are opened inside the main form.

Any idea what's wrong?

[eny]

Part of the code is:

Part of the answer: it all works OK for me.

[Iede]

That's the "funny" thing, I have programs (most trivial ones) where the above works fine, and some (non-trivial) programs where it doesn't. Could it be a compiler setting and if so, how could I check this?

[eny]

What I meant to say was: there is nothing wrong with the isolated code fragment so that is not the problem (I hope, or else there might be a problem with Lazarus or FPC).
The problem most likely lies somewhere else.

My crystal ball came up with: are you using threads? Any (form) code in dll's? Other events like timers that interrupt the normal message flow?
etc.

[Iede]

No, nothing of these...

Oops  there was a timer running and not disabled while opening the inputbox. I disabled it before the inputbox and now it works ok. Thanks a lot!!!