How do I get rid of the Spark List selection indicator entirely? I don't want the rectangular indicator when the mouse hovers over an item, and I don't want the color to change when the mouse is clicked.
You'll have to extend default item renderer (ItemRenderer for instance) and set autoDrawBackground to false. And then use your item renderer in a list.
See this document for more information on spark item renderers.
Thanks, I already had a custom itemRenderer that I'd copied from another project of mine, and sure enough I had set autoDrawBackground to true in it. *facepalm*