1 Qt加载SVG图片

QTreeWidgetItem *item = new QTreeWidgetItem;
//svg_path为SVG图片路径
QSvgRenderer *svg_render = new QSvgRenderer(svg_path);
QPixmap *pixmap = new QPixmap(32, 32);
pixmap->fill(Qt::transparent);
QPainter painter(pixmap);
svg_render->render(&painter);
QIcon ico(*pixmap);
item->setIcon(1, ico);

2 Qt改变SVG图片颜色

QTreeWidgetItem *item = new QTreeWidgetItem;
QString path = svg_path;
QFile file(path);
file.open(QIODevice::ReadOnly);
QByteArray data = file.readAll();
QDomDocument doc;
doc.setContent(data);
file.close();

QString color = "blue";

SetSVGBackColor(doc.documentElement(), "path", "fill", color);

QByteArray svg_content = doc.toByteArray();
QSvgRenderer *svg_render = new QSvgRenderer(svg_content);
QPixmap *pixmap = new QPixmap(32, 32);
pixmap->fill(Qt::transparent);
QPainter painter(pixmap);
svg_render->render(&painter);
QIcon ico(*pixmap);
item->setIcon(0, ico);

void SetSVGBackColor(QDomElement &elem, QString strtagname, QString strattr, QString strattrval);

void SetSVGBackColor(QDomElement &elem, QString strtagname, QString strattr, QString strattrval)
{
    if (elem.tagName().compare(strtagname) == 0)
    {
        QString before_color = elem.attribute(strattr);
        elem.setAttribute(strattr, strattrval);
        QString color = elem.attribute(strattr);
    }
    for (int i = 0; i < elem.childNodes().count(); i++)
    {
        if (!elem.childNodes().at(i).isElement())
        {
            continue;
        }
        SetSVGBackColor(elem.childNodes().at(i).toElement(), strtagname, strattr, strattrval);
    }
}