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Repaint problem

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  • H Offline
    H Offline
    hmartinez
    wrote on last edited by
    #1

    Hello,

    I am using a structure for displaying some icons as follows:

    QGraphicsScene that contains a custom QGraphicsWidget which contains several custom QGraphicsLayoutItem.

    Everything works fine when using local images. But when using online images, I have a kind of refreshing problem. I download the image with the approach explained "here":http://qt-project.org/wiki/Download_Data_from_URL and assign it to a QPixmap.

    I have experienced a very strange behaviour. When the QGraphicsWidget is displayed, the icon is drawn like if it was cropped and, after that(without closing my application), when I click in any other window, the icon is re-drawn correctly. So, as soon as my application loses the focus, the icon is correctly drawn. It seems like I need to do a repaint or something like that, but I don't know where and/or how.

    Any help would be appreciated.

    Thank you in advance.

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    • G Offline
      G Offline
      giordi
      wrote on last edited by
      #2

      Maybe you can attach an update call of the ui to some events or even to a qtimer?

      Coding is powaaaaa

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      • H Offline
        H Offline
        hmartinez
        wrote on last edited by
        #3

        Thank you for your reply. I tried that (adding an update call to the SLOT called when the SIGNAL is emitted), but then I get only the cropped version of the logo. If I do not add the update, then the image does not appear at all until I change the focus to another application.

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        • N Offline
          N Offline
          NicuPopescu
          wrote on last edited by
          #4

          have you tried different ViewportUpdateMode? or before calling update() in slot try to do a dummy resize() of widget

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          • H Offline
            H Offline
            hmartinez
            wrote on last edited by
            #5

            It is working now with the resize before the update, thank you!

            I had previously solved the problem showing a dummy splashscreen without image, so it was doing the trick, but I think resizing is a better approach.

            Thank you again!

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