The QMediaPlayer object does not have a valid service on Ubuntu 16.04

[nekitamtip]

Hi all,

I'm trying to create a simple video player using Python3.5 / Qt5 / PySide2 (5.11.2) on Ubuntu 16.04, but I'm getting an error when trying to play the video: The QMediaPlayer object does not have a valid service.

I found that this can be caused by missing some gstreamer library, so I tried to install some gstreamer related libraries, but that didn't help:

• libgstreamer1.0-0
• libgstreamer1.0-dev
• libgstreamer-plugins-base1.0-dev
• libgstreamer-plugins-good1.0-dev
• gstreamer1.0-plugins-base
• gstreamer1.0-plugins-good
• gstreamer1.0-tools
• libqt5gstreamer-1.0-0
• libqt5gstreamer-dev
• qt5gstreamer-dbg
• qtgstreamer-plugins-qt5

Here is the code I'm trying to run:

import sys
from PySide2 import QtCore, QtWidgets, QtMultimedia, QtMultimediaWidgets

video_path = "some/path/to/video.mp4"

class VideoPlayer(QtWidgets.QWidget):

    def __init__(self, parent=None):
        super(VideoPlayer, self).__init__(parent)

        self.media_player = QtMultimedia.QMediaPlayer(None, QtMultimedia.QMediaPlayer.VideoSurface)
        video_widget = QtMultimediaWidgets.QVideoWidget()
        layout = QtWidgets.QVBoxLayout()
        layout.addWidget(video_widget)
        self.setLayout(layout)
        self.media_player.setVideoOutput(video_widget)
        self.media_player.error.connect(self.handle_error)

    def open_file(self, file_name):
        self.media_player.setMedia(QtMultimedia.QMediaContent(QtCore.QUrl.fromLocalFile(file_name)))

    def play(self, file_path):
        self.open_file(file_path)
        self.media_player.play()

    def handle_error(self):
        print(self.media_player.errorString())


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

    player = VideoPlayer()
    player.resize(320, 240)
    player.show()
    player.play(video_path)

    sys.exit(app.exec_())

Has anyone experienced the same problem?