Re: TForm inside a TThread

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#25

From: Bruce Roberts
Date: Fri, 06 Jul 2001 08:03

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"Sterling Bates" <noone@nowhere.com> wrote in message
news:T1d17.12112$E93.2145422@news1.telusplanet.net...
> I'm use several TThreads to spawn instances of the same form multiple
times;

> This tends to create interesting errors (window handle no longer valid) on
> the Release of the form, and the message "Canvas does not allow drawing"
> when activating a form (this primarly caused, it seems, by TRichEdit).
>
> Another poster mentioned that only the main VCL thread properly handles
> forms, but need to know if there's an elegant way to work with this.
>
> Note: I *do* need to pop up multiple instances of the same form -- I'm
open
> to suggestions on other ideas.

The VCL is not thread safe. What you are trying to do will simply not work.

But you don't need threads to do what you want. Instead set Action to caFree
in the form's OnClose and use the following code like the following (shows 2
copies of the same form)

tMyForm.Create (Application).Show;
tMyForm.Create (Application).Show;

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From: "Bruce Roberts" <ber@bounceitattcanada.xnet>
Newsgroups: comp.lang.pascal.delphi.components.misc,borland.public.delphi.winapi
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Subject: Re: TForm inside a TThread
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