//! [0]
void MyGroupBoxWidget::initStyleOption(QStyleOption *option) const
{
    QGraphicsWidget::initStyleOption(option);
    if (QStyleOptionGroupBox *box = qstyleoption_cast<QStyleOptionGroupBox *>(option)) {
        // Add group box specific state.
        box->flat = isFlat();
        ...
    }
}
//! [0]


//! [1]
setTabOrder(a, b); // a to b
setTabOrder(b, c); // a to b to c
setTabOrder(c, d); // a to b to c to d
//! [1]


//! [2]
// WRONG
setTabOrder(c, d); // c to d
setTabOrder(a, b); // a to b AND c to d
setTabOrder(b, c); // a to b to c, but not c to d
//! [2]