使用QItemDelegate绘制图标

class IconDelegate : public QItemDelegate
{
public:
    void paint(QPainter* painter, const QStyleOptionViewItem& option, const QModelIndex& index) const override
    {
        // 获取数据模型中的图标数据
        QIcon icon = index.data(Qt::DecorationRole).value<QIcon>();

        // 绘制图标
        if (!icon.isNull())
        {
            QRect rect = option.rect;
            int iconSize = rect.height(); // 图标大小与单元格高度相同
            int iconX = rect.x() + (rect.width() - iconSize) / 2; // 图标水平居中
            int iconY = rect.y() + (rect.height() - iconSize) / 2; // 图标垂直居中

            icon.paint(painter, QRect(iconX, iconY, iconSize, iconSize));
        }
    }
};