Security: How to show/hide, by password, QGroupBox in Qt App

I'm trying to prepare my Qt App (in C++) to be used by different user profiles: root user and normal user, so I want to hide specific root options (restricted QGroupBox) in normal user mode, and then when it's needed by a root user he could type it's password (in a security menu option, that I've already coded) to show them. Is that possible in the same GUI? I'm really stuck with this security implementation...

So, how could I code a hidden QGroupBox that will be shown only by root user when it's user/password is typed in the security menu option I mentioned before? How to implement that?

Is there an specific procedure in Qt to do that or any idea in other case?

Thanks a lot!

Last Update: I've used the @The Badger suggestions and have a first version that works just about as I wanted.

There are a few options:

Each time before the widget is drawn/shown, check what level of access the user has and depending on that show or hide controls:

void MyWidget::showEvent(QShowEvent * event) {
    if(d_admin == true) {
        ui->myAdminEdit->setVisible(true);
    } else {
        ui->myAdminEdit->setVisible(false);
    }
    /* Or one line */
    ui->myAdminButton->setVisible(d_admin);
}

Or you connect a signal to show all of the admin widgets based on status:

/* In some constructor */   
ui->myAdminEdit->setVisible(false);
ui->myAdminButton->setVisible(false);
connect(autClass, SIGNAL(adminLoggedIn(bool)), ui->myAdminEdit, SLOT(setVisible(bool)));
connect(autClass, SIGNAL(adminLoggedIn(bool)), ui->myAdminButton, SLOT(setVisible(bool)));

/* And then after authentication */
isAdmin = authenticate(username, password);
emit adminLoggedIn(isAdmin);

After the emit the widgets will become visible.