Qt adding child widget in resizeEvent

I have a widget W deriving from QFrame with layout set to an instance of QVBoxLayout. I wonder if the following resizeEvent implementation is correct or is it going to cause an infinite loop:

void W::resizeEvent(QResizeEvent *event) {
    for (/* some condition based on the new size of this widget */) {
        // Infinite loop or not?
        qobject_cast<QVBoxLayout *>(layout())->addWidget(new QWidget());
    }
}

So far it worked for me, is this by pure luck?