如何在我的Qt应用程序中对小部件进行分组？

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    ui->setupUi(this);

    QWidget *groupWidget = new QWidget(this);
    QVBoxLayout *groupLayout = new QVBoxLayout(groupWidget);

    QLabel *label1 = new QLabel("Label 1", groupWidget);
    QLabel *label2 = new QLabel("Label 2", groupWidget);
    QLabel *label3 = new QLabel("Label 3", groupWidget);

    groupLayout->addWidget(label1);
    groupLayout->addWidget(label2);
    groupLayout->addWidget(label3);

    QVBoxLayout *mainLayout = new QVBoxLayout(ui->centralWidget);
    mainLayout->addWidget(groupWidget);
}