[lazarus] Progressbar control fix

[Micha Nelissen]

Mattias Gaertner wrote:
> On Wed, 25 Jun 2003 20:36:54 +0200
>> The 'Smooth' property does not work yet, it needs to be set when the
>> control is created. Apparantly, you cannot set it later on, using
>> SetWindowLong, as the code now tries to. Can a window recreate be
>> forced within handling the LM_SETPROPERTIES message handler?
>
> Hmm. As far as I can see, LM_SETPROPERTIES is only called in
> ApplyChanges, and this is now only called after Loading, on
> initializing the window and on property change.

FYI: ApplyChanges is also called when Min,Max,Smooth,... are set. Example:

procedure TProgressBar.SetMax(Value: Integer);
begin
   if FMax <> Value then
   begin
      FMax := Value;
      ApplyChanges;
   end;
end;

> So, yes, you can recreate the Handle. But make sure, you only do it,
> when properties has really changed. Otherwise InitializeWnd will loop.

Does this mean I have to detect the case that LM_SETPROPERTIES is called
from InitializeWnd separately?

Another Q: would it be possible to pass extra information about what has
changed? For LM_SETPROPERTIES, Data is unused, maybe we can specify
LMS_PROGRESSBAR_MIN, LMS_PROGRESSBAR_SMOOTH, etc... ? Other controls could
have other flags like LMS_SCROLLBAR_RANGE. (LMS_SCROLLBAR_RANGE could have
the same value as LMS_PROGRESSBAR_MIN, it's a different control). Then we
won't have to check the complete current state of the object versus the
wanted state.

Regards,

Micha.