pyqt example pong (snippet)

Python pyqt (gui) example 'pong'

Modules used in program:

• import sys

pong

Python pyqt example: pong

#!/usr/bin/env python


#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
## All rights reserved.
##
## This file is part of the examples of PyQt.
##
## $QT_BEGIN_LICENSE:BSD$
## You may use this file under the terms of the BSD license as follows:
##
## "Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are
## met:
##   * Redistributions of source code must retain the above copyright
##     notice, this list of conditions and the following disclaimer.
##   * Redistributions in binary form must reproduce the above copyright
##     notice, this list of conditions and the following disclaimer in
##     the documentation and/or other materials provided with the
##     distribution.
##   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
##     the names of its contributors may be used to endorse or promote
##     products derived from this software without specific prior written
##     permission.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
## $QT_END_LICENSE$
##
#############################################################################


import sys

from PyQt5.QtCore import pyqtSlot, QCoreApplication, QMetaObject, QObject
from PyQt5.QtDBus import QDBusConnection


class Pong(QObject):

    @pyqtSlot(str, result=str)
    def ping(self, arg):
        QMetaObject.invokeMethod(QCoreApplication.instance(), 'quit')

        return "ping(\"%s\") got called" % arg


if __name__ == '__main__':
    app = QCoreApplication(sys.argv)

    if not QDBusConnection.sessionBus().isConnected():
        sys.stderr.write("Cannot connect to the D-Bus session bus.\n"
                "To start it, run:\n"
                "\teval `dbus-launch --auto-syntax`\n");
        sys.exit(1)

    if not QDBusConnection.sessionBus().registerService('org.example.QtDBus.PingExample'):
        sys.stderr.write("%s\n" % QDBusConnection.sessionBus().lastError().message())
        sys.exit(1)

    pong = Pong()
    QDBusConnection.sessionBus().registerObject('/', pong,
            QDBusConnection.ExportAllSlots)

    sys.exit(app.exec_())

Useful links

• Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
• Install PyQt: https://pythonbasics.org/install-pyqt/