Problem with background image

[qt890]

Hi, I have a window with a Qwt barchart and I need to display a background image that fills all the window.

The best I could get was:
img.JPG

As you can see, the image isn't displayed correctly. I've overridden MainWindow's resizeEvent() method this way in main.c:

void MainWindow::resizeEvent(QResizeEvent*)
{
    QPixmap bkgnd(":/files/image.png");
    bkgnd = bkgnd.scaled(this->size(), Qt::IgnoreAspectRatio);
    QPalette palette;
    palette.setBrush(QPalette::Background, bkgnd);
    this->setPalette(palette);
}

void MainWindow::resizeEvent(QResizeEvent*)
{
    QPixmap bkgnd(":/files/image.png");
    bkgnd = bkgnd.scaled(this->size(), Qt::IgnoreAspectRatio);
    QPalette palette;
    palette.setBrush(QPalette::Background, bkgnd);
    this->setPalette(palette);
}

To copy to clipboard, switch view to plain text mode 

And commented in barchart.cpp:

//setAutoFillBackground( true );
//setPalette( Qt::white );
//canvas()->setPalette( QColor( "LemonChiffon" ) );

//setAutoFillBackground( true );
//setPalette( Qt::white );
//canvas()->setPalette( QColor( "LemonChiffon" ) );

To copy to clipboard, switch view to plain text mode 

The original image is:
image.png

Using bkgnd = bkgnd.scaled(this->size(), Qt::KeepAspectRatioByExpanding); produces the same output.

How can I solve it?

[Uwe]

How can I solve it?

Depends on what you want to do.

If you really want to have the image as background of the main window you probably need to make the widgets of the plot having no background. But I would overload the paintEvent drawing the image instead of trying to set the background brush as the palette is something that is inherited by the children.

Uwe

[qt890]

Thanks for your reply Uwe. Yes, I want to have the image as background of the main window.

I've tried to overload paintEvent methods this way:

void BarChart::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setBackgroundMode(Qt::TransparentMode);
}

void BarChart::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setBackgroundMode(Qt::TransparentMode);
}

To copy to clipboard, switch view to plain text mode 

void MainWindow::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    QPixmap bkgnd(":/files/image.png");
    painter.drawPixmap(QPoint(0,0), bkgnd);
}

void MainWindow::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    QPixmap bkgnd(":/files/image.png");
    painter.drawPixmap(QPoint(0,0), bkgnd);
}

To copy to clipboard, switch view to plain text mode 

But the output is:
img.JPG