1. Qtablewidget insert button, flexibly delete the line, and display the line number in one column

QTableWidget Insert button

ui->tableWidget->setIndexWidget(ui->tableWidget->index(row, "button"), button);

Flexibly delete this bank

    lds_pushbutton *button = qobject_cast<lds_pushbutton *>(this->sender());
    if(button == 0)
        return;
    QModelIndex index = ui->tableWidget->indexAt(button->pos());
    if(!index.isValid())
        return;
    ui->tableWidget->removeRow(index.row());

A column shows the line number

Set the proxy for this column , The code is as follows

    QStyleOptionViewItemV4 opt;
    opt = option;
    initStyleOption(&opt, index);
#if QT_VERSION >= QT_VERSION_CHECK(5,0,0)
    const QWidget *widget = option.widget;
#else
    const QStyleOptionViewItemV3 *v3 = qstyleoption_cast<const QStyleOptionViewItemV3 *>(&option);
    const QWidget *widget = v3? v3->widget : 0;
#endif
    QStyle *style = widget? widget->style() : QApplication::style();

    if(opt.state & QStyle::State_Selected)
        painter->setPen(opt.palette.brush(QPalette::HighlightedText).color());
    else
        painter->setPen(opt.palette.brush(QPalette::Text).color());
    opt.text = QString::number(index.row() + 1);
    style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);