Meanwhile, just for the code you show what is painer->stroe() at the start, and why do you have a painter->save() at the end? Normally you save painter state at the start of your code and restore it at the end, if anything you seem to be doing the opposite?

Pick one that works for you.

Meanwhile, just for the code you show what is painer->stroe() at the start, and why do you have a painter->save() at the end? Normally you save painter state at the start of your code and restore it at the end, if anything you seem to be doing the opposite?

The first, thank you answer.

But there are some exception. For instance, a column has a QItemDelegate,it likes

void NameDelegate(QPainter* painer, const QStyleOptionVitwItem& op, const QModelIndex& modelindex)const {
    painer->stroe();
    //draw rect for some kind of important tip
    painter->fillRect(op.x()  + 2, 
                    op.y() + 2, 
                    op.width() - 4,
                    op.height() - 4,
                    QBrush(QColor(Qt::yellow);

    //draw name text
    QString name = index->model()->data(Qt::DisplayRole).toString();
    QRect txtRect(op.x()  + 4,op.y() + 4, op.width() - 8,op.height() - 8);
    painter->drawText(txtRect, Qt::AlignCenter, name);

    painter->save();
}
                                    

A column set this NameDelegate (Inherits QItemDelegate), if i use QSS,like selection-color,it will lead all background-color of this NAME column change to white,but as you see, i need this colum show some special background-color( a Rect but don't fill full item)

So do you have any better ideas?

QTableView

The color and background of the selected item is styled using selection-color and selection-background-color respectively.

E.g. https://doc.qt.io/qt-6/stylesheet-examples.html#customizing-qtableview

QTableView {
    selection-background-color: ...
}

Otherwise probably need to see your code.