[Lazarus] Modal Window Crashes on Mac OS X 10.15 Beta (Catalina)

[tobiasgiesen at gmail.com]

Hello,
I found that the code must be corrected like this to avoid an Access
Violation if an event occurs before the aloop field is set.

  if Assigned(aloop) and not isrun then begin
     isrun:=true;
     Result:=nil;
     aloop();
     terminate(nil);
     exit;
     end;

Kind Regards,

Tobias Giesen
Super Flexible Software GmbH & Co. KG

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On Wed, 12 Jun 2019 15:10:17 -0400
Dmitry Boyarintsev via lazarus <lazarus at lists.lazarus-ide.org> wrote:

> On Wed, Jun 12, 2019 at 11:48 AM Zoë Peterson via lazarus <
> lazarus at lists.lazarus-ide.org> wrote:
> 
> > "Swizzling" is the name for replacing the Objective C method pointers
> > using method_exchangeImplementations.  It's not the same as overriding it.
> >
> 
> Quite an interesting technique. I'm quite confident it's being heavily used
> for Javascript.
> (I guess it's somewhat natural for reflective languages to use it)
> 
> Though I'd consider going that low level as a last resort, rather than a
> permanent solution.
> 
> thanks,
> Dmitry

Kind Regards,
Tobias Giesen

Super Flexible Software GmbH & Co. KG
Buddenstr. 29-31
48143 Münster, Germany
www.superflexible.com
www.tgtools.com

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