[C++-sig] inheritance and virtual callbacks

[Matthew Scouten]

all right, yes. I forgot that. mea culpa.
but it did not fix the problem :

>>> import busybox
>>> class myBar(busybox.bar):
...     def __init__( self ):
...             busybox.bar.__init__( self )
...     def FooCallback(self):
...             print "this is a foo callback"
...     def BarCallback(self):
...             print "this is a bar callback"
...
>>> b = myBar()
>>> busybox.backcaller(b)
atemptting bar callback
this is a bar callback
default foo called
>>>

See?  still calls  the wrong function.

On Tue, Jun 3, 2008 at 2:28 PM, Roman Yakovenko <roman.yakovenko at gmail.com>
wrote:

> 2008/6/3 Matthew Scouten <matthew.scouten at gmail.com>:
> > So I have 2 classes, foo and bar. bar is a subclass of foo. Both bar and
> foo
> > have virtual functions intended to be overridden form python.
> >
> > struct foo
> > {
> >     foo(){} ;
> >     foo(int init_x, int init_y){x=init_x;y=init_y;};
> >     int x;
> >     int y;
> >
> >     virtual void FooCallback(){std::cout << "default foo called" <<
> > std::endl;};
> > };
> >
> > struct bar : foo
> > {
> >     bar(){} ;
> >     bar(int init_x, int init_y, int init_z):foo(init_x,init_y){z =
> init_z;};
> >
> >     virtual void BarCallback(){std::cout << "default bar called" <<
> > std::endl;};
> >
> >     int z;
> > };
> >
> > struct foo_wrapper : foo , wrapper<foo>
> > {
> >     foo_wrapper();
> >     foo_wrapper(const foo& f);
> >     foo_wrapper(int init_x, int init_y);
> >
> >     virtual void FooCallback();
> > };
> >
> > void foo_wrapper::FooCallback()
> > {
> >     std::cout << "atemptting foo callback" << std::endl;
> >     if (override func = this->get_override("FooCallback"))
> >     {
> >         func();
> >         return;
> >     }
> >     else
> >         std::cout << "foo callback function not found" << std::endl;
> > }
> >
> > foo_wrapper::foo_wrapper(const foo& exch): foo(exch), wrapper<foo>(){}
> > foo_wrapper::foo_wrapper(): foo(), wrapper<foo>(){}
> > foo_wrapper::foo_wrapper(int init_x, int init_y) : foo(init_x,init_y),
> > wrapper<foo>(){}
> >
> > struct bar_wrapper: bar, wrapper<bar>
> > {
> >     bar_wrapper();
> >     bar_wrapper(const bar& b);
> >     bar_wrapper(int init_x, int init_y, int init_z);
> >
> >     virtual void BarCallback();
> > };
> >
> > bar_wrapper::bar_wrapper(const bar& exch): bar(exch), wrapper<bar>(){}
> > bar_wrapper::bar_wrapper(): bar(), wrapper<bar>(){}
> > bar_wrapper::bar_wrapper(int init_x, int init_y, int init_z) :
> bar(init_x,
> > init_y, init_z), wrapper<bar>(){}
> >
> > void bar_wrapper::BarCallback()
> > {
> >     std::cout << "atemptting bar callback" << std::endl;
> >     if (override func = this->get_override("BarCallback"))
> >     {
> >         func();
> >         return;
> >     }
> >     else
> >         std::cout << "bar callback function not found" << std::endl;
> > }
> >
> > void backcaller(bar& b)
> > {
> >     b.BarCallback();
> >     b.FooCallback();
> > }
> >
> > BOOST_PYTHON_MODULE(busybox)
> > {
> >     class_<foo_wrapper>("foo")
> >         .def(init<>())
> >         .def(init<int, int>())
> >         .ENABLE_COPY(foo)
> >         .def_readwrite("x", &foo::x )
> >         .def_readonly ("y", &foo::y )
> >         ;
> >
> >     class_<bar_wrapper, bases<foo> >("bar")
> >         .def(init<>())
> >         .def(init<int,int,int>())
> >         .ENABLE_COPY(bar)
> >         .def_readwrite("z", &bar::z)
> >         ;
> >
> >     def("backcaller", &backcaller);
> > }
> >
> > in python:
> >>>> import busybox
> >>>> class myBar(busybox.bar):
>
>
> add __init__
>
> def __init__( self ):
>    busybox.bar.__init__( self )
>
>
> > ...     def FooCallback(self):
> > ...             print "this is a foo callback"
> > ...     def BarCallback(self):
> > ...             print "this is a bar callback"
> > ...
> >>>> b = myBar()
> >>>> busybox.backcaller(b)
> > atemptting bar callback
> > this is a bar callback
> > default foo called
> >>>>
> >
> > So the question is: why is the default FooCallback in foo getting called
> > rather then the FooCallback in myBar?
> > What can I do about it?
> >
> >
> > _______________________________________________
> > C++-sig mailing list
> > C++-sig at python.org <C%2B%2B-sig at python.org>
> > http://mail.python.org/mailman/listinfo/c++-sig
> >
> >
>
>
>
> --
> Roman Yakovenko
> C++ Python language binding
> http://www.language-binding.net/
> _______________________________________________
> C++-sig mailing list
> C++-sig at python.org <C%2B%2B-sig at python.org>
> http://mail.python.org/mailman/listinfo/c++-sig
>
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