TableView slow vertical scrolling with 300+ columns

[Ed Kennard]

Hi Kevin, Nir,

I also dug out those two bug reports and agree neither are close enough.  However, it seems to be general consensus that in order to properly address the issue, TableView's virtualisation would need to be changed to support columns in addition to rows, and that the extra complexity through the rest of the control's features would not be a worthwhile trade-off.

So might it be better to submit a new feature request to develop a separate and leaner control entirely, geared much more towards viewing large datasets without all the bells and whistles of a TableView?




On 25/01/2020, 15:39, "Kevin Rushforth" <kevin.rushforth at oracle.com> wrote:

    I took a quick look and didn't see one that was close enough to this, so 
    I think it's worth submitting a new bug report. The closest I found were 
    JDK-8166956 [1] and JDK-8185887 [2].
    
    I also would be interested to know whether others have run into this in 
    their applications.
    
    -- Kevin
    
    [1] https://bugs.openjdk.java.net/browse/JDK-8166956
    [2] https://bugs.openjdk.java.net/browse/JDK-8185887
    
    
    On 1/25/2020 2:10 AM, Nir Lisker wrote:
    > Hi Ed,
    >
    > Try to search JBS [1] for this issue. If you don't find one, you can submit
    > it through bugs.java.com, though I suspect this is known.
    >
    > I don't know the technicalities of VirtualFlow in TableView, so can't help
    > there.
    >
    > - Nir
    >
    > [1] https://bugs.openjdk.java.net/issues/?jql=component %3D javafx
    >
    > On Sat, Jan 25, 2020 at 3:39 AM Ed Kennard <ed at kennard.net> wrote:
    >
    >> Hi everyone,
    >>
    >> I’m new to the list, so by way of a short introduction, I’ve been working
    >> with JavaFX for the last 4 years developing a commodities trading risk
    >> management system from the ground up for a software company I co-founded in
    >> London.  All our code is written in Scala, the functional style of which is
    >> essential for the mathematical heavy lifting needed on the backend, but
    >> which also lends itself really well to UI programming and working with
    >> JavaFX.  I’m enthusiastic about JavaFX and would love to make a
    >> contribution to the project.
    >>
    >> At the center of our product is an extension of the TableView control
    >> that’s responsible for displaying all the output from our pivot reporting
    >> engine.  Depending on how the user configures the layout of their pivot
    >> reports, sometimes there are a legitimately large number of columns
    >> (300+).  When that happens, while the horizontal scrolling remains
    >> perfectly smooth, the vertical scrolling degrades to a somewhat juddery
    >> state and CPU usage spikes.
    >>
    >> I found an issue raised about this in 2019 on the old JFX GitHub repo here…
    >> https://github.com/javafxports/openjdk-jfx/issues/409
    >>
    >> …but I’m not sure whether, per Kevin’s suggestion at the bottom, it was
    >> ever submitted through the correct channels.  I can confirm that the test
    >> code included there by “yososs” on 20th May 2019 perfectly illustrates the
    >> problem I’m experiencing.  The same person seems to have a fairly clear
    >> theory on what is causing the problem, too - see their follow-up comment on
    >> 12 Sept 2019.
    >>
    >> So, my questions to the list are:
    >>
    >>
    >>    1.  Has anyone seen this issue raised anywhere else?
    >>    2.  If yes, has anyone taken a look into it yet, and possibly even found
    >> a fix?
    >>    3.  If no to both of the above, shall I submit it through the correct
    >> channels then have a crack at fixing myself?  Or is the issue likely to be
    >> a much deeper and far-reaching one than I’m anticipating?
    >>
    >> Many thanks
    >>
    >> Ed
    >>