Heatmap colors incorrect when chart legend disabled

Flow
1

It seems the Heatmap chart type in Vaadin Charts 3.0.0 mangles the colors–whether using discrete Stops or minColor + maxColor on the ColorAxis–when the chart’s Legend is disabled. I’ve tested this by adding a button to the page that simply toggles Legend.enabled and redraws the chart.

Legend enabled: Colors display as intended
Legend disabled: Colors become “muted” (red turns to brownish-orange; orange turns to brown; green stays about the same)

In the end my goal is to produce a heatmap with no visible legend, or at least a legend with no numeric labels, but it seems overriding the Legend label formatter has no effect.

2

Hi Steve,

It looks like this is an issue in the underlying chart library.

As a workaround adding the following configuration to the color axis should make it work correctly when hiding the legend:

        config.getColorAxis().setStartOnTick(false);

        config.getColorAxis().setEndOnTick(false);

Hope this helps,

Guille

3

Hi Guillermo,

Thanks so much, this workaround is definitely effective as tested in https://github.com/skradel/vaadinheatmapdemo.

As an aside, one way to hide the legend data labels is to set a format string of " "; “” reverts to the default, and I didn’t have any luck with further efforts via a custom JS formatter.

Thanks,
Steve

4

Glad to hear it worked!