QCameraInfo::availableCameras() is not listing the used camera

    QTimer* m_timer = new QTimer(this);
    connect(m_timer, &QTimer::timeout, [](){
    const auto cameras = QCameraInfo::availableCameras();
    if (cameras.isEmpty())
    {
    qWarning() << "no camera is available";
    }
    for (const auto& cam : cameras)
    {
    qDebug() << cam.deviceName();
    }
    });
    m_timer->start(100);