if(item->checkState(0) == Qt::Checked) {
        selectItem(item);
    } else if(item->checkState(0) == Qt::Unchecked) {
        unselectItem(item);
    }
    QTreeWidgetItem *it = item;
    while(it->parent()) {
        const int count = it->parent()->childCount();
        bool hasPartiallyChecked = false,
             hasChecked = false,
             hasUnchecked = false;
        for(int i = 0; i < count; i++) {
            QTreeWidgetItem *itt = it->parent()->child(i);
            switch (itt->checkState(0)) {
            case Qt::Checked: hasChecked = true; break;
            case Qt::Unchecked: hasUnchecked = true; break;
            case Qt::PartiallyChecked: hasPartiallyChecked = true; break;
            }

            if(hasPartiallyChecked || (hasChecked && hasUnchecked)) {
                hasPartiallyChecked = true;
                break;
            }
        }
        it->parent()->setCheckState(0, hasPartiallyChecked ? Qt::PartiallyChecked :
                                    (!hasChecked ? Qt::Unchecked : Qt::Checked));
        if(it->parent()->checkState(0) == Qt::Checked ||
           it->parent()->checkState(0) == Qt::Unchecked) {
            for(int i = 0; i < count; i++) {
                it->parent()->child(i)->setCheckState(0, it->parent()->checkState(0));
            }
        }
        it = it->parent();
    }