[PyQt] Subclassing a Qt non-QObject class

[Phil Thompson]

On 10/05/2019 02:50, Wallboy wrote:
> Hello,
> 
> I'm working with QNetworkCookieJar and QNetworkCookie in PyQt5. I would 
> like
> a custom QNetworkCookie class to add some additional attributes and 
> methods
> of my own.
> 
> I would like it so that when I insert cookie/s into the 
> QNetworkCookieJar
> and retrieve them later from the cookie jar, they would return my 
> custom
> subclass instance. However it seems when I insert a cookie instance of 
> my
> subclass into the jar, the subclass information is lost later on when I
> retrieve the cookies from the jar.
> 
> Is this because QNetworkCookie is not a QObject? I don't know the inner
> details of how the PyQt bindings work when converting classes from 
> PyQt->Qt
> and vice versa.
> 
> Is there a way I could achieve what I want in PyQt?

The issue isn't whether the class is a QObject or not, it is how the 
instance is passed - a pointer or a const reference. In this case it is 
a const reference so the jar takes a copy of the cookie and it can only 
copy what it knows about, ie. the base QNetworkCookie. It wouldn't work 
in C++ either.

Phil