Popup calendar windows coordinates

[Tomek <morales inet24 pl>]

Hi!
I'd like to popup a calendar widget just under button, which opens it.
The calendar widget is located in window object with no windowmanager
frame. So on the button click signal, the window->show() is triggered.

That works well, but I'd like to pass coordinates to this window to make
it appear just under the calling button. So i need button height and
width and it's top/left coordinates. How to obtain this info?

Maybe you know some application written in C++ using gtkmm/glademm, that has
this functionality done?

Regards
Teel