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Thread: [model/view] slow refresh on big table

  1. #1
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    Default [model/view] slow refresh on big table

    Hi,
    I am using QTableView with a rather big model under (1500x30 cells).
    When I try to scroll it is horribly slow. I tried to see what's going on by
    placing a breakpoint in ::data(QModelIndex, int) and the debugger
    and the window with the table side by side hoping not to interfere too much
    on the refresh mecanism : dream on !
    The backingstore mecanism seems to want to erase the background everytime
    the window gets the focus (and when the debugger stops at a breakpoint,
    the window loses focus and regain it when you hit the run button).
    Anyone has a tip for measuring refresh time in another way, counting the
    number of times the model/view framework call ::data on the same cell for
    a same refresh occasion ?
    Thx in advance.
    Last edited by lauranger; 17th May 2006 at 13:11.

  2. #2
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    Default Re: [model/view] slow refresh on big table

    What kind of model do you use?

  3. #3
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    Default Re: [model/view] slow refresh on big table

    I use an implementation of QAbstractTableModel with
    a QSortFilterProxyModel in between.
    (I was writing a much more dataful version of this message
    when the spirit of the web formulars played me a bad trick).
    I feel that the performance problem is not with the implementation
    I wrote but with the number of rows it presents and the way
    Qt seems to handle refreshes. I'd like to know from where could
    I trace refresh start and refresh end.
    Had anybody faced such slowliness with big model ?
    Last edited by lauranger; 17th May 2006 at 17:07.

  4. #4
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    Default Re: [model/view] slow refresh on big table

    If someone knows how to do this this would be great. I am also having the same issue.

  5. #5
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    Default Re: [model/view] slow refresh on big table

    How do you know it is the same issue?

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