[Vala] How to implement a D-Bus interface to a Object ?

["G.S.Alex" <sthots gmail com>]

As the title.
There has been some examples showed how to register a object to the
bus. But when I run it I got :

                 WARNING **: Object does not implement any D-Bus interface

Thought the code works fine .

I konw I can get code by dbus-binding-tool from XML files in C . Is
there any way to do this in Vala ? Could I just use the Interfaces
writen in Vala?