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Plotting graph from outside paint event function+ error:Paint device returned engine 0



  • Hi,
    I am plotting a graph by painting outside paintevent which runs correctly in my linux desktop.And same application when i ran in IMX environment(for which qt is ported),i am getting error message as QWidget::paintEngine: Should no longer be called QPainter::begin: Paint device returned engine == 0, type: 1 .
    Even i set the attribue for WA_PaintOutsidePaintEvent true for qframe of ui.

    Do i need to include any library to solve it..?



  • AFAIK, you can only paint on non-widget paint engines outside of the paintevent, like on a QImage.



  • if i plot ECG graph on qimage or qpixmap, i wont get proper heart beat (for 180 i will get 237 --- data is missing, painting taking time).



  • Please adjust your topic. It's not sufficient to paste the complete error message here. You get more attention with a good, short and descriptive title. Just hit the edit link right to your first post.


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