---
author: ''
category: ''
date: 2010/07/24 20:37
description: ''
link: ''
priority: ''
slug: BB905
tags: kde, open source, programming, pyqt, python, qt
title: This is why Qt (and PyQt) are cool
type: text
updated: 2010/07/24 20:37
url_type: ''
---
Alejandro Dolina once wrote (and this is from memory that's probably 25 years old) of a round table discussing "What's Tango?", and how after two hours of discussing the nature, characteristics and history of tango, one of the members of the panel picked up a bandoneón, played `"El apache argentino" <http://tinysong.com/tmXs>`_ stood up and left without saying a word.

So, why are Qt and PyQt cool?

`Audio player widget: <http://code.google.com/p/kakawana/source/browse/trunk/kakawana/audioplayer.py>`_

.. code-block:: python

    # -*- coding: utf-8 -*-

    import sys, os
    from PyQt4 import QtCore, QtGui, uic
    from PyQt4.phonon import Phonon
    import icons_rc

    class AudioPlayer(QtGui.QWidget):
        def __init__(self, url, parent = None):

            self.url = url

            QtGui.QWidget.__init__(self, parent)
            self.setSizePolicy(QtGui.QSizePolicy.Expanding,
                QtGui.QSizePolicy.Preferred)


            self.player = Phonon.createPlayer(Phonon.MusicCategory,
                Phonon.MediaSource(url))
            self.player.setTickInterval(100)
            self.player.tick.connect(self.tock)

            self.play_pause = QtGui.QPushButton(self)
            self.play_pause.setIcon(QtGui.QIcon(':/icons/player_play.svg'))
            self.play_pause.clicked.connect(self.playClicked)
            self.player.stateChanged.connect(self.stateChanged)

            self.slider = Phonon.SeekSlider(self.player , self)

            self.status = QtGui.QLabel(self)
            self.status.setAlignment(QtCore.Qt.AlignRight |
                QtCore.Qt.AlignVCenter)

            self.download = QtGui.QPushButton("Download", self)
            self.download.clicked.connect(self.fetch)

            layout = QtGui.QHBoxLayout(self)
            layout.addWidget(self.play_pause)
            layout.addWidget(self.slider)
            layout.addWidget(self.status)
            layout.addWidget(self.download)

        def playClicked(self):
            if self.player.state() == Phonon.PlayingState:
                self.player.pause()
            else:
                self.player.play()

        def stateChanged(self, new, old):
            if new == Phonon.PlayingState:
                self.play_pause.setIcon(QtGui.QIcon(':/icons/player_pause.svg'))
            else:
                self.play_pause.setIcon(QtGui.QIcon(':/icons/player_play.svg'))

        def tock(self, time):
            time = time/1000
            h = time/3600
            m = (time-3600*h) / 60
            s = (time-3600*h-m*60)
            self.status.setText('%02d:%02d:%02d'%(h,m,s))

        def fetch(self):
            print 'Should download %s'%self.url

    def main():
        app = QtGui.QApplication(sys.argv)
        window=AudioPlayer(sys.argv[1])
        window.show()
        # It's exec_ because exec is a reserved word in Python
        sys.exit(app.exec_())

    if __name__ == "__main__":
        main()


`Video player widget:  <http://code.google.com/p/kakawana/source/browse/trunk/kakawana/videoplayer.py>`_

.. code-block:: python

    import sys, os
    from PyQt4 import QtCore, QtGui, uic
    from PyQt4.phonon import Phonon
    import icons_rc

    class VideoPlayer(QtGui.QWidget):
        def __init__(self, url, parent = None):

            self.url = url

            QtGui.QWidget.__init__(self, parent)
            self.setSizePolicy(QtGui.QSizePolicy.Expanding,
                QtGui.QSizePolicy.Preferred)


            self.player = Phonon.VideoPlayer(Phonon.VideoCategory,self)
            self.player.load(Phonon.MediaSource(self.url))
            self.player.mediaObject().setTickInterval(100)
            self.player.mediaObject().tick.connect(self.tock)

            self.play_pause = QtGui.QPushButton(self)
            self.play_pause.setIcon(QtGui.QIcon(':/icons/player_play.svg'))
            self.play_pause.clicked.connect(self.playClicked)
            self.player.mediaObject().stateChanged.connect(self.stateChanged)

            self.slider = Phonon.SeekSlider(self.player.mediaObject() , self)

            self.status = QtGui.QLabel(self)
            self.status.setAlignment(QtCore.Qt.AlignRight |
                QtCore.Qt.AlignVCenter)

            self.download = QtGui.QPushButton("Download", self)
            self.download.clicked.connect(self.fetch)
            topLayout = QtGui.QVBoxLayout(self)
            topLayout.addWidget(self.player)
            layout = QtGui.QHBoxLayout(self)
            layout.addWidget(self.play_pause)
            layout.addWidget(self.slider)
            layout.addWidget(self.status)
            layout.addWidget(self.download)
            topLayout.addLayout(layout)
            self.setLayout(topLayout)

        def playClicked(self):
            if self.player.mediaObject().state() == Phonon.PlayingState:
                self.player.pause()
            else:
                self.player.play()

        def stateChanged(self, new, old):
            if new == Phonon.PlayingState:
                self.play_pause.setIcon(QtGui.QIcon(':/icons/player_pause.svg'))
            else:
                self.play_pause.setIcon(QtGui.QIcon(':/icons/player_play.svg'))

        def tock(self, time):
            time = time/1000
            h = time/3600
            m = (time-3600*h) / 60
            s = (time-3600*h-m*60)
            self.status.setText('%02d:%02d:%02d'%(h,m,s))

        def fetch(self):
            print 'Should download %s'%self.url

    def main():
        app = QtGui.QApplication(sys.argv)
        window=VideoPlayer(sys.argv[1])
        window.show()
        # It's exec_ because exec is a reserved word in Python
        sys.exit(app.exec_())

    if __name__ == "__main__":
        main()

...