Qt中如下代码加载图片是否会造成内存泄漏

[dianyancao]

结束函数on_pushButton_clicked()调用后，graphicsView是否持有子对象scene的指针，scene持有子对象image的指针？

void MainWindow::on_pushButton_clicked()
{
    QGraphicsScene* scene=new QGraphicsScene;
    QPixmap* image=new QPixmap("C:/test/2.bmp");
    scene->addPixmap(*image);
    ui->graphicsView->setScene(scene);
    ui->graphicsView->resize(image->width() + 10, image->height() + 10);
    ui->graphicsView->show();

    //delete scene;
    //delete image;
}

[jdwx]

引用 2 楼 heksn 的回复:

这里的image完全可以使用局部变量

+1

[dianyancao]

如下函数，执行多次，是不是每次执行ui->graphicsView->setScene(scene)时，会delete之前的scene，然后再绑定新的scene？

void MainWindow::on_pushButton_clicked()
{
    QGraphicsScene* scene=new QGraphicsScene;
    QPixmap image("C:/test/2.bmp");
    scene->addPixmap(image);
    ui->graphicsView->setScene(scene);
    ui->graphicsView->resize(image.width() + 10, image.height() + 10);
    ui->graphicsView->show();
}

[dianyancao]

的确被析构了。

// Remove the previously assigned scene.
    if (d->scene) {
        disconnect(d->scene, SIGNAL(changed(QList<QRectF>)),
                   this, SLOT(updateScene(QList<QRectF>)));
        disconnect(d->scene, SIGNAL(sceneRectChanged(QRectF)),
                   this, SLOT(updateSceneRect(QRectF)));
        d->scene->d_func()->removeView(this);
        d->connectedToScene = false;

        if (isActiveWindow() && isVisible()) {
            QEvent windowDeactivate(QEvent::WindowDeactivate);
            QApplication::sendEvent(d->scene, &windowDeactivate);
        }
        if(hasFocus())
            d->scene->clearFocus();
    }

Q_INLINE_TEMPLATE void QList<T>::node_destruct(Node *n)
{
    if (QTypeInfo<T>::isLarge || QTypeInfo<T>::isStatic) delete reinterpret_cast<T*>(n->v);
    else if (QTypeInfo<T>::isComplex) reinterpret_cast<T*>(n)->~T();
}

[Inhibitory]

QPixmap* image=new QPixmap("C:/test/2.bmp"); // delete image需要 delete scene不需要

[写不动代码的人]

这里的image完全可以使用局部变量