void MainWindow::onShuttle(float x)
{
    if (x == 0) {
        m_player->pause();
    } else if (x > 0) {
        m_player->play(10.0 * x);
    } else {
        m_player->play(20.0 * x);
    }
}
void MainWindow::onShuttle(float x)
{
    if (x == 0) {
        m_player->pause();
    } else if (x > 0) {
        m_player->play(10.0 * x);
    } else {
        m_player->play(20.0 * x);
    }
}