[PyQt] QMainWindow bug?

[Mailing List SVR]

Hi Erik,

attacched is a small sample of what I'm doing in my app, I have a dialog
that require some time to open, to speed up the things I store it in a
global object and use this global object to reopen the dialog,

this seems to work, I'm reusing the same dialog from different central
widget, some times (I'm unable to reproduce) I see in the logs:

RuntimeError: underlying C/C++ object has been deleted

so I added a try except when I open the dialog, until today noone
reported segfault, what do you think about this usage?

thanks
Nicola

Il giorno ven, 21/01/2011 alle 08.47 +0100, Erik Janssens ha scritto:
> Hi,
> 
> I wrote some general documentation around these
> issues, with regard to Camelot development, but
> it might be of use to others as well :
> 
> http://downloads.conceptive.be/downloads/camelot/doc/sphinx/build/advanced/development.html
> 
> all remarks/corrections are welcome.
> 
> Regards,
> 
> Erik
> 
> On Thu, 2011-01-20 at 10:22 +0100, Mailing List SVR wrote:
> > Ok, in a my pyqt app (I'm still using pyqt-4.7.x), I have a dialog that
> > require much time to open so I keep a reference to it in a app global
> > variable and I use this reference to reopen the dialog after the first
> > time. This seems to work and the dialog open much quicker, however in
> > some undeterminated cases I get:
> > 
> > RuntimeError: underlying C/C++ object has been deleted
> > 
> > when I get this error I recreate the dialog and update the global
> > reference,
> > 
> > can you please explain the right way to keep a reference in python to a
> > qt object?
> > 
> > thanks
> > NIcola
> > 
> > 
> > Il giorno mer, 19/01/2011 alle 23.47 +0100, Erik Janssens ha scritto:
> > > there was a change in sip/pyqt from 4.8.1 to 4.8.2 regarding
> > > the detection of objects deleted by qt but still referenced in
> > > python (which is the case here).  in 4.8.1 sip/pyqt tried to
> > > detect this to avoid segfaults.  this detection however brought
> > > other issues with it, therefor the detection was turned off again
> > > in 4.8.2
> > > 
> > > the solution is not to keep references in python of objects
> > > owned by qt when they might get deleted.
> > > 
> > > On Wed, Jan 19, 2011 at 12:36 PM, Mailing List SVR
> > > <lists at svrinformatica.it> wrote:
> > > > I can confirm the segfault:
> > > >
> > > > - linux, kernel 2.6.36
> > > > - python 2.7.1
> > > > - pyqt 4.8.2
> > > > - qt 4.7.1
> > > >
> > > > works fine with PySide,
> > > >
> > > > Nicola
> > > >
> > > >
> > > > Il giorno mer, 19/01/2011 alle 08.36 +0100, Vicent Mas ha scritto:
> > > >> 2011/1/18 Nick Gaens <mail at nickgaens.com>:
> > > >> > - Win7 64bit
> > > >> > - Python 2.6.6 (r266:84297, Aug 24 2010, 18:46:32) [MSC v.1500 32 bit
> > > >> > (Intel)] on win32
> > > >> > - Qt v4.7.0
> > > >> > - PyQt GPL v4.8.1 for Python v2.6
> > > >> > Result: no crashes, works like a charm..
> > > >> >
> > > >>
> > > >> Hi,
> > > >>
> > > >> I get the crash also on Windows Vista 32bit (again Python 2.6 and PyQt 4.8.2)
> > > >>
> > > >> Vicent
> > > >>
> > > >
> > > > _______________________________________________
> > > > PyQt mailing list    PyQt at riverbankcomputing.com
> > > > http://www.riverbankcomputing.com/mailman/listinfo/pyqt
> > > >
> > > _______________________________________________
> > > PyQt mailing list    PyQt at riverbankcomputing.com
> > > http://www.riverbankcomputing.com/mailman/listinfo/pyqt
> > 
> 
> 
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