 1  MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
2  {
3    ui->setupUi(this);
4    ui-> volumeLCD->setPalette(Qt::red);
5    ui-> volumeLabel->setAlignment(Qt::AlignHCenter);
6    ui->volumeDial->setNotchesVisible(true);
7    ui->volumeDial->setMinimum(0);
8    ui->volumeDial->setMaximum(100);
9    QObject::connect(ui->volumeDial, SIGNAL(valueChanged(int)),
                 ui->volumeLabel,   SLOT(setNum(int)));
10   QObject::connect(ui->volumeDial, SIGNAL(valueChanged(int)),
                 ui->volumeLCD ,   SLOT(display(int)));
11  }