QPixmap seems to be null but it isn't

[satoshi]

Hi all,
I've a strange problem setting a QPixmap on a QLabel. I call a thread which sets the QPixmap on the QLabel. That's the code I'm using:

QPixmap *pxm = new QPixmap((QString("C:/image.jpg")));
    if(!pxm->isNull())
    {
    	printf("Pixmap isn't null! %dx%d\n", this->width(), pxm->height());
    	this->a->w->imageLabel->setImage(this->pxm);
    }
    else
    {
    	printf("Pixmap is null!\n");
    }

QPixmap *pxm = new QPixmap((QString("C:/image.jpg")));
    if(!pxm->isNull())
    {
    	printf("Pixmap isn't null! %dx%d\n", this->width(), pxm->height());
    	this->a->w->imageLabel->setImage(this->pxm);
    }
    else
    {
    	printf("Pixmap is null!\n");
    }

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If I put it in the run() function of the thread, it clears the image that the imageLabel was showing before (you see a gray background). If I put it in the costructor of the thread instead, it works. But in both it prints:
"Pixmap isn't null! 320x274
I set the image. 320x274 32 (183, 175, 172)"

Thats the method setImage of imageLabel:

void G2_ImageLabel::setImage(QPixmap *pxm)
{
	QImage img = pxm->toImage();
	QRgb px = img.pixel(10, 10);
	printf("I set the image. %dx%d %d (%d, %d, %d)\n", pxm->width(), pxm->height(), pxm->depth(), qRed(px), qGreen(px), qBlue(px));
	this->setPixmap(*pxm);
}

void G2_ImageLabel::setImage(QPixmap *pxm)
{
	QImage img = pxm->toImage();
	QRgb px = img.pixel(10, 10);
	printf("I set the image. %dx%d %d (%d, %d, %d)\n", pxm->width(), pxm->height(), pxm->depth(), qRed(px), qGreen(px), qBlue(px));
	this->setPixmap(*pxm);
}

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I don't know what I'm doing wrong. Please help me!

Thank you, Dario

(sorry for my english)