Gradient background in vaadin chart: creative ideas? How to embed an svg gr

Flow
1

Gradient backgrounds are not supported in Vaadin Charts 6 (for Vaadin 14+) according to https://vaadin.com/docs/v14/charts/java-api/charts-breaking-changes-in-version-6.html

However, it is possible with highcharts https://www.highcharts.com/docs/chart-design-and-style/gradients-shadows-and-patterns

I thought it might still be possible with vaadin charts but don’t know if my ideas could theoretically work (and I am just doing it wrong) or if it is really impossible. My ideas:

  1. combine whatever chart type with a heat map, creating some sort of “pixellated” gradient
    In my case I’d want to combine a bubble chart with the “fake” heatmap background chart but I don’t really know how to combine these two.
  2. Have an (invisible) svg gradient embedded in the site that one could refer to in the fill property. This seems possible (see https://fvsch.com/svg-gradient-fill/ ), however how could I embed a css accessible svg gradient in a vaadin component? This should even be supported in IE11 (to keep vaadin 14s IE11 compatibility alive) and would be enough for my use case.

No 2. seems to be the way to try, the only thing missing should be a way to embed the svg code into the resulting vaadin page - how could I achieve this?

2

Hi Raphael,

We are actually working on reintroducing the java styling API for Vaadin Charts in the next version, which should make this just as easy as it was back in the Vaadin 8 version of charts (https://demo.vaadin.com/charts4/#PieWithGradientFill).

Keep an eye out for Vaadin 17 (https://vaadin.com/roadmap), in which we expect to include the new Charts version.

3

Hi Rolf

Thank you for taking the time to answer - this is great news! As per your roadmap, enhancements are generally backported to the latest LTS version, does that include vaadin charts as well? Meaning: if I extrapolate your versioning scheme correctly, at around the time Vaadin 17 is released, (some of) it’s features could be backported to Vaadin 14.4 - would that also include the charts enhancements?

4

Hi Raphael

Can’t promise anything, but probably.

Backporting decisions are made case-by-case once we have a feeling for the stability, quality etc of the new feature (assuming that it’s fundamentally compatible with the LTS in the first place of course). If we feel that we want to do some tweaks before bringing it to the current LTS it could be postponed to a later minor. In this case the probability of finding any blockers for backporting seems fairly low.