QPaintDevice: Must construct a QApplication before a QPaintDevice

[boris.smirnov at gmail.com]

On Feb 28, 10:22 am, Phil Thompson <p... at riverbankcomputing.co.uk>
wrote:
> On Wednesday 28 February 2007 9:00 am, boris.smir... at gmail.com wrote:
>
>
>
>
>
> > On Feb 28, 9:07 am, boris.smir... at gmail.com wrote:
> > > On Feb 28, 8:56 am, Phil Thompson <p... at riverbankcomputing.co.uk>
>
> > > wrote:
> > > > On Tuesday 27 February 2007 11:09 pm, shredwheat wrote:
> > > > > When your programs stops with the error, it should also be printing a
> > > > > stack trace. This is a list of all the functions that have been
> > > > > called when Python had the problem.
>
> > > > > You shouldn't have to do anything extra to get the stack trace.
>
> > > > The error is raised in Qt and aborts immediately. It never gets back to
> > > > Python to generate a trace.
>
> > > > He needs to produce a short and complete test which demonstrates the
> > > > problem, then we can point out where the QPaintDevice is being created.
>
> > > > Phil
>
> > > OK, but before I do a complete test, could anybody tell/explain me why
> > > the same file is working on Windows?
> > > Did anybody already meet with something similar Win vs. Linux?
>
> > > b.
>
> > Here is my simple script:
>
> > import sys
> > from qt import *
> > class Optimizer(QWidget):
> >    def __init__(self, parent = 0):
> >       QWidget.__init__(self)
> >       QGridLayout(self)
> > if __name__ == '__main__':
> >    a = QApplication (sys.argv)
> >    mywidget = Optimizer()
> >    a.exec_loop()
>
> > This produces this:
> > > python qt_script_bs_070228.py
>
> > QPaintDevice: Must construct a QApplication before a QPaintDevice
>
> > Any suggestions here?
>
> It works fine for me.
>
> > Thanks
>
> > BTW: One question:
> > when I use "import qt" instead of "from qt import *" I get this error:
> > Traceback (most recent call last):
> >   File "mscarideidtool_bs_070228.py", line 4, in ?
> >     class Optimizer(QWidget):
> > NameError: name 'QWidget' is not defined
>
> > What is the difference between "import qt" and "from qt import *" ? I
> > thought that these are the same.
>
> The first creates a new namespace called "qt" and imports the module's objects
> into it. To reference those objects you have to include the namespace name.
>
> The second imports the module's objects into the current namespace.
>
> Phil- Hide quoted text -
>
> - Show quoted text -

OK, I have to apologize because I didn't mention that I use python
version 2.2.1, could it be the problem here? Bugs or something? I have
to use this version since it was delivered with a software that we use
here.