Paint a scrollbar

[humbleguru]

Hi! I'm trying to paint a scrollbar in a QGraphicsItem by calling QStyle::drawComplexControl(). It works like a charm for vertical scrollbars. However, it doesn't work properly for horizontal scrollbars in some styles, especially in the oxygen style.

I have made a simple test case by reimplementing QWidget:aintEvent(). This is what I do:

void paintEvent(QPaintEvent *event)
{
		QStyleOptionSlider option;
		option.minimum = 0;
		option.maximum = 50;
		option.orientation = Qt::Horizontal;
		option.pageStep = 10;
		option.singleStep = 1;
		option.sliderPosition = 0;
		option.sliderValue = 0;
		option.activeSubControls = QStyle::SC_None;
		option.subControls = QStyle::SC_All;
		option.state = QStyle::State_Enabled;
		option.rect = QRect(0, 0, 200, 16);
 
		QPainter painter(this);
		style()->drawComplexControl(QStyle::CC_ScrollBar, &option, &painter);
 
		event->accept();
	}

void paintEvent(QPaintEvent *event)
{
		QStyleOptionSlider option;
		option.minimum = 0;
		option.maximum = 50;
		option.orientation = Qt::Horizontal;
		option.pageStep = 10;
		option.singleStep = 1;
		option.sliderPosition = 0;
		option.sliderValue = 0;
		option.activeSubControls = QStyle::SC_None;
		option.subControls = QStyle::SC_All;
		option.state = QStyle::State_Enabled;
		option.rect = QRect(0, 0, 200, 16);

		QPainter painter(this);
		style()->drawComplexControl(QStyle::CC_ScrollBar, &option, &painter);

		event->accept();
	}

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Am I missing something? Should I do it in a different way?

Notice in the screenshots how it's totally screwed up in the Oxygen style while it displays fine in Plastique. In Windows, the buttons show up/down arrows instead of left/right arrows. If you change it to Qt::Vertical (and give a proper size) it displays fine in all those styles.

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Added after 13 minutes:

I answer to myself: I had to add QStyle::State_Horizontal to the state.

[tbscope]

Note that you can also just use a scrollbar widget in a scene or item