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Thread: Help on QGraphicsItem::paint please

  1. #1
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    Default Help on QGraphicsItem::paint please

    Hi,

    My QGraphicsScene has a scroll bar. When I scroll it, the QGraphicsItem:aint option's exposedRect is always fixed to the viewport's size, I have to redraw the entire item even though most of the item has not changed.

    What I hope is to only redraw the exposed part of the item when scroll bar is moved, because it takes a lot of time to draw the item.

    I have used
    QGraphicsView::setViewportUpdateMode( QGraphicsView::MinimalViewportUpdate );

    Any suggestions please?

  2. #2
    Join Date
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    Default Re: Help on QGraphicsItem::paint please

    Have you set the QGraphicsItem Flag:

    Qt Code:
    1. setFlag(QGraphicsItem::ItemUsesExtendedStyleOption);
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    It's mentioned in the doc that the exposedRect member depend on it

  3. The following user says thank you to mitch for this useful post:

    lni (3rd May 2012)

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