How to re-add a custom widget?

Question

Qt

Column::Column(QWidget *parent)
      : QListWidget(parent)
{
    Button *button = new Button(this);
    {
        connect(button, &Button::clicked,
                this, &Column::slot_addCard);
    }

    QListWidgetItem *buttonItem = new QListWidgetItem(this);
    buttonItem->setSizeHint(button->sizeHint()); // change size
    addItem(buttonItem);
    setItemWidget(buttonItem, button);

    qDebug() << buttonItem;
    qDebug() << button;
}

void Column::slot_addCard()
{
    const int COUNT = this->count() - 1;
    Button *button = dynamic_cast<Button*>(itemWidget(item(COUNT)));
    QListWidgetItem *buttonItem = this->takeItem(COUNT);

    qDebug() << buttonItem;
    qDebug() << button;

    Card *card = new Card(this);
    QListWidgetItem *cardItem = new QListWidgetItem(this);
    cardItem->setSizeHint(card->sizeHint());
    setItemWidget(cardItem, card);

    addItem(buttonItem);
    setItemWidget(buttonItem, button);  // Segmentation fault !!!
}

Answer 1

Maybe setItemWidget() on a QListWidgetItem object can only be called once? What happens if there is no last line? Reversal just to the fields button fulfills without falling?