[QT5.13.1 on Windows] QMediaPlayer's setMedia() API giving error 5 i.e. QMediaPlayer::ServiceMissingError

[RkTest]

Our is a C++ on windows GUI project which we build using visual studio 2017. For GUI we use QT 5. We dont use qt creator. In one of the widget I have to play a video using QT for which I am trying to use QMediaPlayer. I took a code snippet from the documentation. In the gui we select a file and then click on the play button which is supposed to play the video.

After the call to API setMedia() we see a mediaplayer error 5 i.e. QMediaPlayer::ServiceMissingError. What service is the qt API looking for?

How to play the video using qt api in this c++ windows code?

void signalWidget::handleError()
{
    m_playButton->setEnabled(false);
    const QString errorString = m_mediaPlayer->errorString();
    QString message = "Error: ";
    if (errorString.isEmpty())
        message += " #" + QString::number(int(m_mediaPlayer->error()));
    else
        message += errorString;
    m_errorLabel->setText(message);

    std::cout << " ERROR = " << message.toStdString() << "\n";
}

void signalWidget::positionChanged(qint64 position)
{
std::cout << " position = " << position << "\n";
    m_positionSlider->setValue(position);
}

void signalWidget::durationChanged(qint64 duration)
{
std::cout << " duration = " << duration << "\n";
    m_positionSlider->setRange(0, duration);
}

void signalWidget::setPosition(int position)
{
std::cout << " position = " << position << "\n";
    m_mediaPlayer->setPosition(position);
}

void signalWidget::mediaStateChanged(QMediaPlayer::State state)
{
    std::cout << " state = " << state << "\n";
    switch(state) {
    case QMediaPlayer::PlayingState:
        m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
        break;
    default:
        m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
        break;
    }
}

 void signalWidget::MediaError(QMediaPlayer::Error error)
 {
  std::cout << " Media Error: " << error << "\n";
 }

 void signalWidget::ChangedStatus(QMediaPlayer::MediaStatus status)
 {
  std::cout << " Status changed to: " << status << "\n";
 }

void signalWidget::play()
{
std::cout << " currentMedia = " << m_mediaPlayer->currentMedia().canonicalUrl().toString().toStdString() << 
                                                    ", playerState = " << m_mediaPlayer->state() << "   E\n";

    switch (m_mediaPlayer->state()) {
    case QMediaPlayer::PlayingState:
        m_mediaPlayer->pause();
        break;
    default:
        m_mediaPlayer->play();
        break;
    }

    std::cout << " playerState = " << m_mediaPlayer->state() << ", playerMediaState = " << m_mediaPlayer->mediaStatus() << "\n";
}

void signalWidget::setUrl(const QUrl &url)
{
    m_errorLabel->setText(QString());
    setWindowFilePath(url.isLocalFile() ? url.toLocalFile() : QString());
    **m_mediaPlayer->setMedia(url);**
    m_playButton->setEnabled(true);
std::cout << " currentMedia = " << m_mediaPlayer->currentMedia().canonicalUrl().toString().toStdString() << 
                                                    ", player State = " << m_mediaPlayer->state() <<
                                                    ", player ERROR = " << m_mediaPlayer->error();

}

void signalWidget::openFile()
{
    QFileDialog fileDialog(this);
    fileDialog.setAcceptMode(QFileDialog::AcceptOpen);
    fileDialog.setWindowTitle(tr("Open Movie"));
    QStringList supportedMimeTypes = m_mediaPlayer->supportedMimeTypes();
    if (!supportedMimeTypes.isEmpty())
        fileDialog.setMimeTypeFilters(supportedMimeTypes);
    fileDialog.setDirectory(QStandardPaths::standardLocations(QStandardPaths::MoviesLocation).value(0, QDir::homePath()));
    if (fileDialog.exec() == QDialog::Accepted)
        setUrl(fileDialog.selectedUrls().constFirst());
}

The above code is called as:

signalWidget::signalWidget(int widget_id)
{
        m_mediaPlayer = new QMediaPlayer(this, QMediaPlayer::VideoSurface);
        videoWidget = new QVideoWidget;
    
        QAbstractButton *openButton = new QPushButton(tr("Open..."));
        connect(openButton,SIGNAL(clicked()),this,SLOT(openFile()));

        m_playButton = new QPushButton;
        m_playButton->setEnabled(false);
        m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
        connect(m_playButton, SIGNAL(clicked()), this, SLOT(play()));

        m_positionSlider = new QSlider(Qt::Horizontal);
        m_positionSlider->setRange(0, 0);
        connect(m_positionSlider, SIGNAL(sliderMoved()), this, SLOT(setPosition()));

        m_errorLabel = new QLabel;
        m_errorLabel->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Maximum);

        m_errorLabel->setAutoFillBackground(true); // IMPORTANT!
        m_errorLabel->setStyleSheet("QLabel { background-color : pink; color : blue; }");

        QBoxLayout *controlLayout = new QHBoxLayout;
        controlLayout->setMargin(0);
        controlLayout->addWidget(openButton);
        controlLayout->addWidget(m_playButton);
        controlLayout->addWidget(m_positionSlider);

        QBoxLayout *layout = new QVBoxLayout;
        layout->addWidget(videoWidget);
        layout->addLayout(controlLayout);
        layout->addWidget(m_errorLabel);
        layout->setMargin(0); //! to avoid wasting spaces with margins
        setLayout(layout);

        m_mediaPlayer->setVideoOutput(videoWidget);
        connect(m_mediaPlayer, SIGNAL(stateChanged()), this, SLOT(mediaStateChanged()));
        connect(m_mediaPlayer, SIGNAL(positionChanged()), this, SLOT(mediaStateChanged()));
        connect(m_mediaPlayer, SIGNAL(durationChanged()), this, SLOT(durationChanged()));
        connect(m_mediaPlayer, SIGNAL(Error()), this, SLOT(handleError()));

}

[Axel Spoerl]

@RkTest
Qt 5.13.1 is out of support. Pls try with a more recent Qt version (>= 6.2)