Scrollable Tkinter widget not threadsafe?

[Peter Abel]

abli <abli at freemail.hu> wrote in message news:<3ef0af9e at andromeda.datanet.hu>...
> The exception you get is 
> 
> RuntimeError: Calling Tcl from different appartment
> 
> You have to do all calls to tkinter from one thread. 
> In the example you give, you create the widget, then start a new thread
> which enters mainloop. This means that you try to use two threads to
> communicate with Tkinter, which causes the exception.
> By moving all tkinter calls, i.e. the lines
>   root=Tkinter.Tk()
>   FrameScollTest (root).pack(fill='both',expand=True)
> into show_widget(), it runs fine.
>     
> Of course, this has nothing to do with the type of widget you want to use,
> a Tkinter.Label behaves the same way.
> 
> Abel Daniel

Thanks very much Daniel,
it works as you described.
I had no RuntimeError, only a TK-Window with nothing that
didn't respond. But I think this behavior depends of the
platform, os-version etc.
What remains unclear for me is that I should start a thread
already with the line:

  root=Tkinter.Tk()

Until now I believed entering threading with

  root.mainloop()

because this worked this way, but only without Scrollbars.

Regards
Peter