Where to place init code (in which event handler) needing custom widget's window mapped?

[David Sillou <silloudavid yahoo fr>]

Hello,
I need to execute various initialization code in a derived widget; That 
code  need to be executed only one time but it also need that widget's 
window is mapped since i need to perform few operation (xine related 
stuff) on that window (GDK object).

Could someone please tell me where is the best place to put that code?

Is there any available documentation that could help me to have a better 
idea of when and why events are fired in a typical widget's life (for 
example: relation between widget's state and events ) ?  It's rather 
difficult to find out in which circumstances events are fired for a 
beginner; Studying xlib (and gtk) helped me  but it remains obscure to me.

Thx a lot for your help.
Have a nice day  (hum... It's night for me)  :-)

DAve