Re: Callback Trouble

From:

"Alf P. Steinbach" <alfps@start.no>

Newsgroups:

comp.lang.c++

Date:

Mon, 19 Nov 2007 14:42:04 +0100

Message-ID:

<13k34le8gei67ed@corp.supernews.com>

* Nashirak:

On Nov 17, 9:49 am, rpbg...@yahoo.com (Roland Pibinger) wrote:

AFAICS, the problem is that member function pointers are not
polymorphic in C++. The following is a Reader's Digest version of your
code with some additions:

Thanks for your responses. I played around with this a little more
this weekend and found that once I made My_Plugin inherit from
PI_PluginAPI in a non-virtual manner, everthing seemed to work and
compile. So by changing:

class My_Plugin : virtual public PI_PluginAPI

to

class My_Plugin : public PI_PluginAPI

Everything seemed to work ok.

It shouldn't. Your error message said you supplied a member function
with signature void (My_Plugin::*)() as actual argument to void
(PI_PluginAPI::*)(const KeyboardEvent*). Do you spot the difference?

Thanks again for your responses. I will take a look at that callback
library.

Take a look at your code first.

Cheers, & hth.,

- Alf

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