[avahi] Avahi interface for Python and Gtk+ 3 main loops

[Andrei Macavei]

Hi,

I am developing a client/server app in Python GTK+3 that uses avahi to 
publish itself on the network while discovering other instances of the 
same service.

I am forced to run two main loops which isn't right.
The Gtk widget MainWindow, that represents the main window of the 
application, is using the main loop to wait for the user to interact 
with it.

When I create the MainWindow object, I also start the avahi service 
which publishes the current service and discovers other relevant network 
services.
The browsing of services with avahi requires a main loop also, because 
of the callback functions that are called when a new service is discovered.

As a results I cannot run two main loops and I get the reasonable error. 
The traceback starts with the call of the main loop in the python file 
representing the avahi service discover client:

RuntimeError: To make asynchronous calls, receive signals or export 
objects, D-Bus connections must be attached to a main loop by passing 
mainloop=... to the constructor or calling dbus.set_default_main_loop(...)

Here is the python code for all 3 classes involved:

1. MainWindow          http://dpaste.com/2PGAGWG
2. ServicePublisher    http://dpaste.com/12B8D62
3. ServiceDiscover     http://dpaste.com/0GZ69HK