possible to add QPointer support?

[Anonymous]

Hi,

First off, thanks for creating this extremely useful library.

Is there any chance of handling QPointer ? I have an object model that handles all QObjects as QPointer<T> - as opposed to raw pointer T* - and PythonQT therefore doesn't recognize the given type 'T' that I  register. Note I'm specifically requesting this w.r.t. the dynamic slot-based approach, not the generator (the latter I suppose could be used to wrap my object model?).

Thanks in advance for any answer!

[Florian Link]

Hm, I am not sure if I understand your right…

Does your API look like this:

QPointer<SomeResult> doSomething(QPointer<SomeObject> object)

and you would like PythonQt to detect the SomeResult / SomeObject types and pass correct QPointers?

Although this is doable (it would need to be implemented in PythonQtConversion), if this is really your API, I have to admit that I do not understand why you use QPointer in such a way?

QPointer is a weak pointer that gets NULLified when the QObject is deleted. But there is no reason to pass it around as QPointers, it should be enough to store a QPointer reference inside of your classes. I can see no advantage of passing them around as a QPointer?!

regards,
Florian

[Anonymous]

Hi Florian,

Correct, and that's a good point, thanks. One issue I have is that I have things like QList < QPointer <T > > as members. So in this case it seemed easier for the functions to return that directly vs. converting it to raw pointers first. And after I did that, it just seemed a nicer API to consistently return QPointers for all cases, since I was immediately building them again upon receipt anyway (slippery slope ;-).

Does that make sense or have I headed off in the wrong direction altogether? In particular, how are QPointer lists generally handled? (And thanks *very much* for any help, I know this is no longer really a PythonQt conversation).

Thanks again!
Jason

[Florian Link]

Since a QList of pointers is not very expensive, I would say you should use QList<SomeObject*> instead.

Regarding QList<QPointer<SomeObject> >, I guess one could get away with using a QList<QPointer<QObject> > implementation,  it should be safe to cast such a QList to the derived QPointer type.

So you could use the PythonQtConv:: registerMetaTypeToPythonConverter() method to register all
versions that you want to support. The conversion method would be similiar to what is done in
PythonQtConvertListOfValueTypeToPythonList (in same file).

regards,
Florian