Is this possible? In a popup I want to have a list with a single row that scrolls to the left and right (kind of like a "covers view" but selection like a normal list).
You should be add a UIList, in the HORIZONTAL_ICON mode, but in the skin file's "IconView" element, set the number of rows to 1. It'd look like the horizontal icon view you get in the video/music/photo library. These screens show it as a 7x3 grid (at least in the default skin it does), but there is no reason your couldnt use it as a grid with only one row.
What do you use for the element names in the UiList constructor for the icon view, "IconView" and "IconItem"? I can't get the list to show up at all but I can with the standard list view using "ListView" and "ListItem"?