[Qt-interest] Convert from a QPixmap into a QByteArray, and back

[Malyushytsky, Alex]

Have you tried using
QDataStream & operator>> ( QDataStream & stream, QPixmap & pixmap )
instead of loadFromData(bytes->data());

This functions might assume different format of data written.

Alex


From: qt-interest-bounces at trolltech.com [mailto:qt-interest-bounces at trolltech.com] On Behalf Of Gabriele Kahlout
Sent: Tuesday, May 18, 2010 2:54 PM
To: qt-interest at trolltech.com
Subject: [Qt-interest] Convert from a QPixmap into a QByteArray, and back

Hello,

In the process of debugging I've found myself unable to assert the following code:
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    const QPixmap screen = QPixmap::grabWindow(QApplication::desktop()->winId());
    QByteArray *bytes = new QByteArray();
    QDataStream out(bytes, QIODevice::WriteOnly);
    out << screen;
    QPixmap* screen1 = new QPixmap();
    screen1->loadFromData(bytes->data());
    std::cout << screen1->save("7777.png", "PNG") << endl;
    std::cout << screen.save("6666.png", "PNG") << endl;
    return a.exec();
}

All I'm doing is trying to convert from a QPixmap into a QByteArray, and back. Although the code is mostly verbatim from QPixmap and QDataStream, it doens't work. Indeed screen1 fails to save into 7777.png.

Your help, fixing this code, is greatly appreciated.

--
Regards,
K. Gabriele

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