Get QImage from QFrame

[sheeeng]

Hi,

How do I get QImage of a QFrame display?

Thanks in advance.

[vishwajeet.dusane]

I am not sure what you meant by that but if you mean getting image set on QFrame then try QPalette class.

[sheeeng]

Hi, I'm not setting QImage on QFrame.

Let me illustrate. There's an example on http://labs.trolltech.com/page/Graphics/Examples page.

Look at the reflection sample. I want to get the QFrame's QImage so that I can manipulate the reflection. In other words, I would like to get all the QLabel, QCheckBox, etc. inside the QFrame to be reflected.

[wagmare]

use QPixmap::grabWindow(QFrame)

or refer Desktop/screenshot example

[vishwajeet.dusane]

ok now i got it. ok then u can use QPixmap::grabWidget() method.

This method will give u entire widget (in you case QFrame) as a pixmap that includes child as well.

[sheeeng]

Hi everyone,

Thanks for showing to use the QPixmap::grabWidget(QWidget*) method.

[sheeeng]

But the reflection also copies the widget background color.

How can I use transparency for the QPixmap?

[aamer4yu]

Did you have a look at the code ? The source code is available for that example .
hers the function for mirrorImage... You can also search for the source code on svn or git.

enum FadeStyle {
    NoFade,
    FadeDown,
    FadeRight,
    FadeUp,
    FadeLeft
};
 
enum MirrorStyle {
    NoMirror,
    MirrorOverX,
    MirrorOverY
};
static inline QImage mirrorImage(const QImage &img, MirrorStyle mirrorStyle=MirrorOverX,
                                 FadeStyle fadeStyle=FadeDown)
{
    QImage tmpImage = img;
    if (mirrorStyle != NoMirror)
        tmpImage = tmpImage.mirrored(mirrorStyle == MirrorOverY,
                                     mirrorStyle == MirrorOverX);
 
    if (fadeStyle != NoFade) {
        QPoint p1, p2;
 
        if (fadeStyle == FadeDown)
            p2.setY(tmpImage.height());
        else if (fadeStyle == FadeUp)
            p1.setY(tmpImage.height());
        else if (fadeStyle == FadeRight)
            p2.setX(tmpImage.width());
        else if (fadeStyle == FadeLeft)
            p1.setX(tmpImage.width());
 
        QLinearGradient gradient(p1, p2);
        gradient.setColorAt(0, Qt::white);
        gradient.setColorAt(0.25, QColor(0, 0, 0, 20));
        gradient.setColorAt(1, Qt::transparent);
 
        QPainter p(&tmpImage);
        p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
        p.fillRect(0, 0, tmpImage.width(), tmpImage.height(), gradient);
        p.end();
    }
    return tmpImage;
}

enum FadeStyle {
    NoFade,
    FadeDown,
    FadeRight,
    FadeUp,
    FadeLeft
};

enum MirrorStyle {
    NoMirror,
    MirrorOverX,
    MirrorOverY
};
static inline QImage mirrorImage(const QImage &img, MirrorStyle mirrorStyle=MirrorOverX,
                                 FadeStyle fadeStyle=FadeDown)
{
    QImage tmpImage = img;
    if (mirrorStyle != NoMirror)
        tmpImage = tmpImage.mirrored(mirrorStyle == MirrorOverY,
                                     mirrorStyle == MirrorOverX);

    if (fadeStyle != NoFade) {
        QPoint p1, p2;

        if (fadeStyle == FadeDown)
            p2.setY(tmpImage.height());
        else if (fadeStyle == FadeUp)
            p1.setY(tmpImage.height());
        else if (fadeStyle == FadeRight)
            p2.setX(tmpImage.width());
        else if (fadeStyle == FadeLeft)
            p1.setX(tmpImage.width());

        QLinearGradient gradient(p1, p2);
        gradient.setColorAt(0, Qt::white);
        gradient.setColorAt(0.25, QColor(0, 0, 0, 20));
        gradient.setColorAt(1, Qt::transparent);

        QPainter p(&tmpImage);
        p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
        p.fillRect(0, 0, tmpImage.width(), tmpImage.height(), gradient);
        p.end();
    }
    return tmpImage;
}

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[sheeeng]

Hi,

Thanks for all the advices.

I manage to get the transparency working by using an heuristic mask and set it to the image.