Make draggable again after drop

Make draggable again after drop


Imagine a photo album organisation tool. Therefore I have 3 divs: one
with all photos (A) uploaded by a user, one for the album
(B=droppable) and one trashcan (C=droppable). You can drag photos from
A to B, or drag photos from B to C. Everything works fine. Dropping
onto B adds a photo to the album, but... after dropping it's not
draggable anymore, although it has the same class as the draggable
from A. It has exactly the same properties. Is there some other step
involved to make the dropped item draggable again that I might be
missing?
Oh, another question: how would you check if an item already exists in
B? (If it already exists the drop should be disabled, or atleast some
indication that the item is already present.)
-Codex