TableView slow vertical scrolling with 300+ columns

[Nir Lisker]

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
>