Problem with QListWidget and paintEvent()

[joksi]

I have inherited QListWidget and rewrote the paintEvent()-function as follows:

void InheritedListWidget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true);
 
    static const QPointF points[3] = {
        QPointF(2,2),
        QPointF(this->width()-2,2),
        QPointF(2,this->height()-2)
    };
    painter.setBrush(Qt::black);
    painter.drawPolygon(points, 3);
}

void InheritedListWidget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true);
    
    static const QPointF points[3] = {
        QPointF(2,2),
        QPointF(this->width()-2,2),
        QPointF(2,this->height()-2)
    };
    painter.setBrush(Qt::black);
    painter.drawPolygon(points, 3);
}

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Now, for some reason when I'm running the program, nothing is painted on the list widget and the application prints to console:

QPainter::begin: Paint device returned engine == 0, type: 1
QPainter::setRenderHint: Painter must be active to set rendering hints
QPainter::setBrush: Painter not active

QPainter::begin: Paint device returned engine == 0, type: 1
QPainter::setRenderHint: Painter must be active to set rendering hints
QPainter::setBrush: Painter not active

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What is wrong with my code?

[birchbay]

You should give viewport to QPainter.

QPainter painter(this->viewport());

QPainter painter(this->viewport());

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See Qt docs:

void QAbstractScrollArea:: paintEvent ( QPaintEvent * event ) [virtual protected]

This event handler can be reimplemented in a subclass to receive paint events (passed in event), for the viewport() widget.

Note: If you open a painter, make sure to open it on the viewport().

[joksi]

Thanks birchbay, this solved my problem!