PySide DBus Integration

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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
 # Get the session bus
 bus = dbus.SessionBus()
 # Get the remote object
 remote_object = bus.get_object("com.example.SampleService",
 # Get the remote interface for the remote object
 iface = dbus.Interface(remote_object, "com.example.SampleWidget")
 except dbus.DBusException:
 # Start the application
 app = QCoreApplication([])
 # Call some methods of the remote interface
 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

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):
# Another method… now with a parameter
 @dbus.service.method("com.example.SampleWidget", in_signature='s', out_signature='')
 def setText(self, value):
# Another one…
 @dbus.service.method("com.example.SampleWidget", in_signature='', out_signature='')
 def exit(self):
# A signal that will be exported to dbus
 @dbus.service.signal("com.example.SampleWidget", signature='')
 def clicked(self):
# Another signal that will be exported to dbus
 @dbus.service.signal("com.example.SampleWidget", signature='')
 def lastWindowClosed(self):
if ''name'' == '''main''':
 app = QApplication([])
 # Use qt/glib mainloop integration to get dbus mainloop working
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."

Running the examples

Copy the client code to a file called and the server to a file called and type:

python &

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.