[PyQt] Python 3 import error

[Thorsten Kampe]

* Hans-Peter Jansen (Thu, 2 Dec 2010 15:47:28 +0100)
> On Thursday 02 December 2010, 14:25:21 Thorsten Kampe wrote:
> > Okay, if I omit the ".toByteArray()", then the application starts
> > with Python 3 - but it doesn't work with Python 2 anymore:
> >
> > self.restoreGeometry(settings.value('Geometry'))
> > TypeError: QWidget.restoreGeometry(QByteArray): argument 1 has
> > unexpected type 'QVariant'
> >
> > Is there a way around that or do I simply have to query the Python
> > version inside the script? Or put in a try "without toByteArray()" if
> > exception, try with "toByteArray()"?!
> 
> Add this before your _first_ PyQt4 import:
> 
> # This is only needed for Python v2 but is harmless for Python v3.
> import sip
> sip.setapi('QVariant', 2)

Actually the solution for my (two) problems is... (see below)
 
> > The - hopefully - last problem with the porting to Python 3:
> > Everything seems to work fine, except closing the application through
> > the menu or toolbar (Alt+F4 works fine):
> >
> > Traceback (most recent call last):
> >   File "my_application-new.pyw", line 32, in on_actionE_xit_triggered
> >     settings.setValue('Geometry',
> > QtCore.QVariant(self.saveGeometry())) TypeError:
> > PyQt4.QtCore.QVariant represents a mapped type and cannot be
> > instantiated
> >
> > this refers to
> > def on_actionE_xit_triggered(self):
> >     settings = QtCore.QSettings()
> >     settings.setValue('Geometry',
> > QtCore.QVariant(self.saveGeometry())) self.close()

import sip
sip.setapi('QVariant', 1)

This will make PyQt4 for Python 3 behave as PyQt4 for Python and the two 
errors above are solved. Not particular pretty (more like an ugly hack) 
but it works...!

Thorsten