qtQuick源码中的loadImage函数

Posted 2023-02-16

【中文标题】qtQuick源码中的loadImage函数

【英文标题】：loadImage function in qtQuick source code

【发布时间】：2017-10-17 15:58:16

【问题描述】：

在 qtQuick 源中。函数loadImage中有一行代码：

QQuickPixmap* pix = new QQuickPixmap();

如果我在canvas上尽量调用这个函数。操作系统分配给这个应用程序的内存会被填满，导致图片失效。请问有没有问题这个源代码？

void QQuickCanvasItem::loadImage(const QUrl& url)


    Q_D(QQuickCanvasItem);
    QUrl fullPathUrl = d->baseUrl.resolved(url);
    if (!d->pixmaps.contains(fullPathUrl)) 
        QQuickPixmap* pix = new QQuickPixmap();
        QQmlRefPointer<QQuickCanvasPixmap> canvasPix;
        canvasPix.adopt(new QQuickCanvasPixmap(pix));
        d->pixmaps.insert(fullPathUrl, canvasPix);

        pix->load(qmlEngine(this)
                , fullPathUrl
                , QQuickPixmap::Cache | QQuickPixmap::Asynchronous);
        if (pix->isLoading())
            pix->connectFinished(this, SIGNAL(imageLoaded()));
    

【参考方案1】：

void QQuickCanvasItem::loadImage(const QUrl& url)


    Q_D(QQuickCanvasItem);
    QUrl fullPathUrl = d->baseUrl.resolved(url);
    if (!d->pixmaps.contains(fullPathUrl)) 
        QQuickPixmap* pix = new QQuickPixmap();
        QQmlRefPointer<QQuickCanvasPixmap> canvasPix;
        canvasPix.adopt(new QQuickCanvasPixmap(pix));
        d->pixmaps.insert(fullPathUrl, canvasPix);

        pix->load(qmlEngine(this)
                , fullPathUrl
                , QQuickPixmap::Cache | QQuickPixmap::Asynchronous);
        if (pix->isLoading())
            pix->connectFinished(this, SIGNAL(imageLoaded()));