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This is why Qt (and PyQt) are cool

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" stood up and left with­out say­ing a word.

So, why are Qt and PyQt cool?

Au­dio play­er wid­get:

# -*- 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:

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()

...

Guest / 2010-07-25 15:12:

You've got an unused icons_rc import in your scripts, FWIW.

Roberto Alsina / 2010-07-25 15:30:

That provides the icons I use as ':/icons/whatever.svg' , it's a resource file compiled using pyrcc4.

The uic import is useless, though.


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