[Qgis-developer] Add Layer to overview

[Michele Mammini]

Dear all,

i'm new on QGis, and i'm starting to develop plugin for my project 
using Python and QT.
I'm able to connect to PostGIS database to query the data and to load 
the Layer into QGis, but i'm not able to load the same layer in the 
Overview windows.
May someone can suggest me which function/class/code allow me to do it?

Thank you,

Michele.