How do I remove white border around QScrollArea?

Radical

I'm trying to edit the source of an app called qcomicbook ( http://qcomicbook.linux-projects.net/ ), to remove an annoying 1px white border which persists in full-screen mode.

First I tried changing the background of the main window black, but it had no effect. Here is the newly compiled app against the designer preview:

!http://img413.imageshack.us/img413/4751/screenshot15j.png(screenshot)!

I tried also setting some border and margin style information but the white border remained, so I looked at the cpp source, searched the Qt docs, and made a few simple edits, but they had no effect.

At first I thought this would be a quick cosmetic fix, but now I assume the developer could not find the cause.

He has this inside PageViewBase.cpp:

@PageViewBase::PageViewBase(QWidget *parent, int physicalPages, const ViewProperties &props)
: QScrollArea(parent)
, m_physicalPages(physicalPages)
, props(props)
, smallcursor(NULL)
{
context_menu = new QMenu(this);
connect(&this->props, SIGNAL(changed()), this, SLOT(propsChanged()));
recalculateScrollSpeeds();

}
@

This inside ContinuousPageView.cpp:

@
ContinuousPageView::ContinuousPageView(QWidget *parent, int physicalPages, const ViewProperties& props)
: PageViewBase(parent, physicalPages, props)
, m_firstVisible(-1)
, m_firstVisibleOffset(0)
, m_y1pos(NULL)
, m_y2pos(NULL)
{
//setFocusPolicy(QWidget::StrongFocus);

QWidget *w = new QWidget(this);

// w->setColor(QPalette::Background, Qt::black);
// adding above line didn't work
//
w->setSizePolicy(QSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding));
m_layout = new QVBoxLayout(w);
m_layout->setContentsMargins(0, 0, 0, 0);
// changing above line didn't change anything
m_layout->setSpacing(0);
m_layout->setAlignment(Qt::AlignCenter);

recreatePageWidgets();
recalculatePageSizes();

setWidget(w);
setWidgetResizable(true);

setBackground(props.background());
setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);

// track scrollbar range changes to restore its relative position
connect(verticalScrollBar(), SIGNAL(rangeChanged(int, int)), this, SLOT(scrollbarRangeChanged(int, int)));

}
@

And this inside ComicMainWindow.cpp:

@
void ComicMainWindow::setupComicImageView()
{
const int n = (sink != NULL ? sink->numOfImages() : 0);
if (view)
{
view->disconnect();
pageLoader->disconnect();
view->deleteLater();
}
const ViewProperties props;
if (cfg->continuousScrolling())
{
view = new ContinuousPageView(this, n, props);
}
else
{
view = new SimplePageView(this, n, props);
}

setCentralWidget(view);
view->setFocus();

reconfigureDisplay();

connect(actionPageTop, SIGNAL(triggered(bool)), view, SLOT(scrollToTop()));
...

}
@

Ideas?

tony

Hi,

QScrollArea is a QFrame descendant. If you set the frame shape to QFrame::NoFrame

setFrameShape(QFrame::NoFrame);

it should disappear ... did I understand your point?

Tony.

Radical

Tony, thanks, but this did not remove the border.

In Qt, is QFrame the only class which has paints a border?

James

tony

Well, I'm not sure that's the only one. QFrame is a QWidget with a border, so I guess that any widget that'd like to be surrounded by a border, can descend directly from QFrame.

Anyway, it's really strange that your border does not disappear. If you place a QScrollArea on a QWidget with Qt Designer, you can test it by yourself and it works (are you sure it's a QScrollArea???)

I can just think about two causes:

a) a particular stylesheet is present, and it draws a border. In this case, you should remove it there.
b) it has a custom paint event. It shouldn't be so difficult to remove any suspicious drawRect inside that method.

Tony.

Radical

Ok, setFrameShape did work actually. The other day I was running make from vi in the wrong dir.

Thanks for the help.

James.