Qt 九宫格贴背景图片

void paintRow(const QPixmap &pix, QPainter &painter, int begin, int y, int width, int h)
{
    while (begin < width-pix.width())
    {
        if (width-pix.width()-begin > pix.width())
        {
            painter.drawPixmap(begin, y, pix.width(), h, pix);
        }
        else
        {
            painter.drawPixmap(begin, y, width-pix.width()-begin, h, pix);
        }
        begin += pix.width();
    }
}

void paintColumn(const QPixmap &pix, QPainter &painter, int x, int begin, int w, int height)
{
    while (begin < height-pix.height())
    {
        if (height-pix.height()-begin > pix.height())
        {
            painter.drawPixmap(x, begin, w, pix.height(), pix);
        }
        else
        {
            painter.drawPixmap(x, begin, w, height-pix.height()-begin, pix);
        }
        begin += pix.height();
    }
}

/**
 * @brief PaintBackground 九宫格贴背景
 * @param pWidget
 *
 *  |1|2|3|   |0|1|2|
 *  |4|5|6|   |3|4|5|
 *  |7|8|9|   |6|7|8|
 *
 */
void PaintBackground(QWidget *pWidget, const QStringList &list)//(QPainter &painter, int width, int height)
{
    QPainter painter(pWidget);
    int width  = pWidget->width();
    int height = pWidget->height();

    QPixmap pix;

    // 四个角贴图
    pix.load(list.at(0));    // 左上角
    if (pix.isNull())
    {
        return;
    }
    painter.drawPixmap(0, 0, pix.width(), pix.height(), pix);
    pix.load(list.at(2));    // 右上角
    painter.drawPixmap(width-pix.width(), 0, pix.width(), pix.height(), pix);
    pix.load(list.at(6));    // 左下角
    painter.drawPixmap(0, height-pix.height(), pix.width(), pix.height(), pix);
    pix.load(list.at(8));    // 右下角
    painter.drawPixmap(width-pix.width(), height-pix.height(), pix.width(), pix.height(), pix);

    // 四条边
    pix.load(list.at(1));    // 上边
    paintRow(pix, painter, pix.width(), 0, width, pix.height());

    pix.load(list.at(7));    // 下边
    paintRow(pix, painter, pix.width(), height-pix.height(), width, pix.height());

    pix.load(list.at(3));    // 左侧边
    paintColumn(pix, painter, 0, pix.height(), pix.width(), height);

    pix.load(list.at(5));    // 右侧边
    paintColumn(pix, painter, width-pix.width(), pix.height(), pix.width(), height);

    // 中心区域贴图
    pix.load(list.at(4));

    int begin = pix.height();
    while (begin < height-pix.height())
    {
        if (height-pix.height()-begin > pix.height())
        {
            paintRow(pix, painter, pix.width(), begin, width, pix.height());
        }
        else
        {
            paintRow(pix, painter, pix.width(), begin, width, height-pix.height()-begin);
        }

        begin += pix.height();
    }
}