LayerList Component adding opacity slider on

JamesVillanueva2 — Mon, 02 Feb 2026 22:12:38 GMT

I am trying to embed an opacity slider in the LayerList Component inside of the listItemCreatedFunction. I get an opacity slider, but CSS formatting from themes never seem to make it to the ESRi based Slider.

Example in CodePen

Any suggestions is greatly appreciated.

Re: LayerList Component adding opacity slider on

Sage_Wall — Mon, 02 Feb 2026 23:11:54 GMT

Hi @JamesVillanueva2 ,

It's likely because of the ShadowDOM preventing from setting the styles of the widget. I'd suggest sticking to the calcite-slider approach current sample app shows for now. If you just want to change the look to be similar to the old dark theme you can set the "calcite-mode-dark" class on the body or on the map as this example shows.
https://codepen.io/sagewall/pen/QwErBGL

In general I'd try to avoid mixing old widgets and the new components if at all possible.

In the next 5.0 release we will have a new slider components including an opacity slider component.

topic Re: LayerList Component adding opacity slider on in ArcGIS JavaScript Maps SDK Questions

LayerList Component adding opacity slider on

Re: LayerList Component adding opacity slider on