[Interest] Container members in abstract base class?

[Constantin Makshin]

Another place to find that information is the documentation on
QGraphicsItem::type(). :-)
On May 23, 2013 10:57 PM, "Jonathan Greig" <redteam316 at gmail.com> wrote:

> I have implemented the type() method for all of my derived classes so that
> qgraphicsitem_cast would work. I just tested it out and apparently it will
> not work unless the value returned is an enum of the class. Returning an
> enum that isn't part of the class fails every time.
> I'm showing this here incase someone else ruins into the same pitfall, as
> qgraphicsitem_cast doesn't explain this in the documentation and the only
> place to find the way it will work is in the examples:
>
> //ENUMFROMINCLUDEDHEADER is greater than UserType
>
> //will not work as a one liner :(
> virtual int type() const { return ENUMFROMINCLUDEDHEADER; }
>
> //will work ONLY if it is named Type
> enum { Type = ENUMFROMINCLUDEDHEADER };
> virtual int type() const { return Type; }
>
> - Swyped from my droid.
>
> On May 23, 2013 12:29 PM, "Constantin Makshin" <cmakshin at gmail.com> wrote:
>
> Yes, qgraphicsitem_cast isn't as powerful as dynamic_cast, but this
> simplicity also makes it faster.
>
> Anyway, Jonathan asked about casting C++ objects and now has several
> methods to choose from. :-)
>
>
>
> On May 23, 2013 9:17 PM, "Jan Kundrát" <jkt at flaska.net> wrote:
> >
> > On Thursday, 23 May 2013 19:04:...
>
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