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QWidget update calls

  • Hello All
    I am experiencing a problem of extra paint requests inside q3scrollview::viewportpaintevent().
    I am doing simple thing of switching my application with another windows application.
    I suppose windows keeps paint buffers and hence should not call the paint event of my widget class.

    Is this correct understanding or something is missing from this ?


  • Lifetime Qt Champion

    Hi and welcome to devnet,

    I can't say whether you're right or wrong, I can only encourage your to update your code to use QScrollView. The Qt3Support module was meant to help the transition to Qt 4.

  • @SGaist
    I was also thinking of migrating to qscrollview.
    But in my context I think this is a generic behaviour. Means, I have a standalone application which just displays a widget inside a qapplication. I have put in debug prints in the paintevent.
    I saw that this is hit each time this application is focussed out and in.

    myScroll* scroll = new myScroll(NULL,0 );
    return application.exec();


  • Lifetime Qt Champion

    Because a focus change will modify how a widget is painted e.g. dimmer color, slightly greyed etc.

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