QGraphicsView::fitInView()

[stella1016]

Anybody knows the implied difference between these pieces of code? Any duplicated updating?
Thanks.

void my_graphicsView::resizeEvent(QResizeEvent *event)
{
setWidth(event->size().width());
setHeight(event->size().height());
 
fitInView(QRectF(0,0,width(),height()),Qt::KeepAsp ectRatioByExpanding);
arrangeNodes();
 
m_scene->setSceneRect(0,0,width(),height());
this->setSceneRect(0,0,width(),height());
 
update();
}

void my_graphicsView::resizeEvent(QResizeEvent *event)
{
setWidth(event->size().width());
setHeight(event->size().height());

fitInView(QRectF(0,0,width(),height()),Qt::KeepAsp ectRatioByExpanding);
arrangeNodes();

m_scene->setSceneRect(0,0,width(),height());
this->setSceneRect(0,0,width(),height());

update();
}

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void my_graphicsView::resizeEvent(QResizeEvent *event)
{
setWidth(event->size().width());
setHeight(event->size().height());
 
fitInView(QRectF(0,0,width(),height()),Qt::KeepAsp ectRatioByExpanding);
arrangeNodes();
 
m_scene->update(0,0,width(),height());
update();
}

void my_graphicsView::resizeEvent(QResizeEvent *event)
{
setWidth(event->size().width());
setHeight(event->size().height());

fitInView(QRectF(0,0,width(),height()),Qt::KeepAsp ectRatioByExpanding);
arrangeNodes();

m_scene->update(0,0,width(),height());
update();
}

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[high_flyer]

Is this home work?

[stella1016]

Is this home work?

fitInView() works.

But it I comment it out, the paiting quality seems to be lower.

In QGraphicsItem's paint(), I have:

painter->setRenderHint(QPainter::SmoothPixmapTransform);
painter->setPen(QPen(Qt::red));
painter->setBrush(QBrush(Qt::gray, Qt::Dense4Pattern));

painter->setRenderHint(QPainter::SmoothPixmapTransform);
painter->setPen(QPen(Qt::red));
painter->setBrush(QBrush(Qt::gray, Qt::Dense4Pattern));

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Actually there is another post which is related to my problem:
http://www.qtcentre.org/threads/4013...gging-blinking

[high_flyer]

fitInView() works.

But it I comment it out, the paiting quality seems to be lower.

Well it might for example, if the fitInView() has to cause scaling up for the drawn elements.