Qt for Python DBusIntegration

To get PySide and DBus working toghether you can use the glib mainloop integration already done in pydbus.

The examples below show how to export Qt objects to Python and emit a D-Bus signal when a Qt signal is emitted. The code comments explain what you need to know about PySide and D-Bus.

Also refer to the dbus-python tutorial.

D-Bus Client

#!/usr/bin/env python
# -'''- coding: utf-8 -'''-

# DBUS Client using PySide integration

import sys
from traceback import print_exc

# import python dbus module
import dbus
# import python dbus GLib mainloop support
import dbus.mainloop.glib
# import QtCore
from PySide.QtCore import'''

# signal handler
def button_clicked():
 print "button clicked"

# main function
if ''name'' == '''main''':

 # Enable glib main loop support
 dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
 # Get the session bus
 bus = dbus.SessionBus()

 try:
 # Get the remote object
 remote_object = bus.get_object("com.example.SampleService",
 "/DBusWidget")
 # Get the remote interface for the remote object
 iface = dbus.Interface(remote_object, "com.example.SampleWidget")
 except dbus.DBusException:
 print_exc()
 sys.exit(1)

 # Start the application
 app = QCoreApplication([])

 # Call some methods of the remote interface
 iface.show()
 iface.setText("Emit signal")
 # connect the DBus signal clicked to the function button_clicked
 iface.connect_to_signal("clicked", button_clicked)
 iface.connect_to_signal("lastWindowClosed", app.quit)

 # enter in the main loop
 app.exec_()

D-Bus Server

#!/usr/bin/env python
#-'''- coding: utf-8 -'''-

# DBUS Server Example of use PySide with PyDBus library

import dbus
import dbus.service
import dbus.mainloop.glib
import random

from PySide.QtCore import'''
from PySide.QtGui import QPushButton, QApplication

# The adaptor, MUST inherit dbus.service.Object
class DBusWidget(dbus.service.Object):
 def ''init''(self, name, session):
 # export this object to dbus
 dbus.service.Object.''init''(self, name, session)

# create a simple widget
 self.widget = QPushButton()
 self.widget.resize(200, 50)

# To export a Qt signal as a DBus-signal, you need to connect it to a method in this class.
 # The method MUST have the signal annotation, so python-dbus will export it as a dbus-signal
 QObject.connect(self.widget, SIGNAL ("clicked()"), self.clicked)
 QObject.connect(QApplication.instance(), SIGNAL ("lastWindowClosed()"), self.lastWindowClosed)

# You can export methods to dbus like you do in python-dbus.
 @dbus.service.method("com.example.SampleWidget", in_signature='', out_signature='')
 def show(self):
 self.widget.show()

# Another method… now with a parameter
 @dbus.service.method("com.example.SampleWidget", in_signature='s', out_signature='')
 def setText(self, value):
 self.widget.setText(value)

# Another one…
 @dbus.service.method("com.example.SampleWidget", in_signature='', out_signature='')
 def exit(self):
 qApp().quit()

# A signal that will be exported to dbus
 @dbus.service.signal("com.example.SampleWidget", signature='')
 def clicked(self):
 pass

# Another signal that will be exported to dbus
 @dbus.service.signal("com.example.SampleWidget", signature='')
 def lastWindowClosed(self):
 pass

if ''name'' == '''main''':
 app = QApplication([])
 # Use qt/glib mainloop integration to get dbus mainloop working
 dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)

session_bus = dbus.SessionBus()
 # Export the service
 name = dbus.service.BusName("com.example.SampleService", session_bus)
 # Export the object
 widget = DBusWidget(session_bus, '/DBusWidget')

print "Running example service."
 app.exec_()

Running the examples

Copy the client code to a file called example-client.py and the server to a file called example-server.py and type:

python example-server.py &
python example-client.py

A small window should appear on screen. Click on the button to emit a Qt signal. The signal will be converted to a D-Bus signal that will be caught by our D-Bus client.