presenting property
The GlassBarItem.sheet whose sheet is up out of the hoisted chrome, or null.
The one exception to the hand-back hoisted describes. The capsule a
sheet morphs out of stays the shell's for as long as the sheet is up: the
morph has emptied it, so nothing of it is drawn above the sheet, and
handing it back would take the anchor out from under the droplet. So
while this is set hoisted is false, leading and actions hold the
real buttons for every other group, and the slot this item's group
occupies keeps its placeholder. A bar drawing its own chrome leaves that
capsule unpainted likewise. The instance is the one that was tapped;
compare by id if the bar rebuilds its items.
Implementation
final GlassBarSheetItem? presenting;