[PyQt] Construct QVariant from object of user type
arve.knudsen at gmail.com
Thu Apr 17 09:44:52 BST 2008
On 4/17/08, Matt Newell <newellm at blur.com> wrote:
> On Wednesday 16 April 2008 14:18:26 Arve Knudsen wrote:
> > On Wed, Apr 16, 2008 at 11:33 AM, Phil Thompson
> > <phil at riverbankcomputing.co.uk> wrote:
> > > On Wednesday 16 April 2008, Arve Knudsen wrote:
> > > > Phil, any comment on this?
> > > >
> > > > Thanks,
> > > > Arve
> > >
> > > Unless you can use the ctor that takes a void* I don't see how you can
> > > expect to extend the functionality of a C++ class from Python.
> > How am I supposed to use the QVariant(int typeOrUserType, const void*
> > copy) constructor from Python? The documentation refers to
> > sip.voidptr, which I know nothing about, and to use qVariantFromValue
> > which isn't defined.
> > I need to store objects of a custom class in QVariants, with a certain
> > type code (QVariant::Type). The reason I need to do this is that
> > QItemEditorFactory is parameterized on QVariant::Type.
> > Arve
> If you look at qmetatype.h, you'll see that it should be possible to create a
> mechanism to register custom python classes as QVariant types. You just need
> to implement Constructor/Destructor methods that call Py_INCREF/Py_DECREF.
> Then for each custom python type call QMetaType::registerType(...). This
> would need to be implemented in c++ with a python interface.
> You could then write a custom QVariant constructor that detects if the python
> object's type is registered, and automatically call the QVariant(int
> type,void*) ctor, or throws an exception for non-registered types.
So I would *have to* do this in C++? Ugh.
> BTW, you don't really have to use QItemEditorFactory. You can use a custom
I know .
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