[SOLVED]Defining QMdiArea background

mbnoimi

Hello folks,

I want to add background image for QMdiArea but without tiling the image, how can I do that?

PS

I tried to use setBackground(img) but it appears tiled background!
!http://i.imgur.com/Aj8qs.png(test)!
I tried to use styleSheet but it shows the image in subWindows instead of Mdi area
@background-image: url(:/img/gnome-graphics.png);
background-repeat : no-repeat;@
!http://i.imgur.com/lvzjE.png(test)!

sigrid

The following "FAQ":http://developer.qt.nokia.com/faq/answer/when_setting_a_background_pixmap_for_a_widget_it_is_tiled_if_the_pixmap_is_ suggests a way of achieving this by reimplementing the resizeEvent() and scaling the image.

mbnoimi

Thanks a lot (I didn't notice that answer although I used search option).

I modified the answer a little bit.
@#ifndef MDIAREA_H
#define MDIAREA_H

#include <QMdiArea>
#include <QResizeEvent>
#include <QPainter>

class MdiArea : public QMdiArea
{
Q_OBJECT
public:
MdiArea(/*QMdiArea clone, */QImage backgroundImage, QBrush backgroundBrush)
{
i = backgroundImage;
b = backgroundBrush;
}
protected:
void resizeEvent(QResizeEvent *resizeEvent)
{
QImage newBackground(resizeEvent->size(), QImage::Format_ARGB32_Premultiplied);
QPainter p(&newBackground);
p.fillRect(newBackground.rect(), b);

    QImage scaled = i.scaled(resizeEvent->size(),Qt::KeepAspectRatio);
    QRect scaledRect = scaled.rect();
    scaledRect.moveCenter(newBackground.rect().center());
    p.drawImage(scaledRect, scaled);
    setBackground(newBackground);
    QMdiArea::resizeEvent(resizeEvent);
}

private:
QImage i;
QBrush b;
};

#endif // MDIAREA_H@

I tried to use that implementation for passing QMdiArea as a copy but it didn't' work because " QMdiArea::QMdiArea(const QMdiArea&) is private"
@ui->mdiArea = new MdiArea(MdiArea(QImage(":/img/gnome-graphics.png"), Qt::red)); // mdiArea is QMdiArea object@

How can I fix this issue?

sigrid

Can you give some more details on what exactly you want to do? Have you created a QMdiArea in Designer and want to use it together with the QMdiArea subclass that was created in code? If so, you can simply "promote ":http://doc.qt.nokia.com/latest/designer-using-custom-widgets.html#promoting-widgets the QMdiArea in Designer to your subclass.

Creating a copy of the QMdiArea is not possible. It is not possible to create copies of QObjects and their subclasses for the reasons outlined in this "FAQ":http://developer.qt.nokia.com/faq/answer/why_is_it_not_allowed_to_copy_qobjects. Instead, you can follow the advice listed "here":https://developer.qt.nokia.com/faq/answer/how_can_i_clone_a_widget if you need to clone a widget

mbnoimi

[quote]Have you created a QMdiArea in Designer and want to use it together with the QMdiArea subclass that was created in code? If so, you can simply promote [doc.qt.nokia.com] the QMdiArea in Designer to your subclass.[/quote]
Yes exactly but I couldn't find QMdiArea in base class drop list of Promoted widgets window!

[quote]Can you give some more details on what exactly you want to do?[/quote]
you can test my trial at [url=http://www.mediafire.com/file/9rebbbdumq982df/MDITest.zip]this link[/url] (it's tiny test don't be afraid).

PS
I'm wondering why these forums don't allow to post attachments this is really sucks.

giesbert

[quote author="mbnoimi" date="1311689985"]PS
I'm wondering why these forums don't allow to post attachments this is really sucks.[/quote]

There were many discussions about that, but the result was, it is complicated due to legal issues.

mbnoimi

Guys could you please help me... I couldn't fix this issue.

sigrid

The QMdiArea is indeed not listed among the promoted widgets. I checked the reason for this with our developers here and QMdiArea is put in an exclude list since it is a container that it is problematic to promote. I see that you are investigating a way around this in this "thread":http://developer.qt.nokia.com/forums/viewthread/8334, and that sounds like a viable approach since QFrame is a container as well.