Change callback in sortable

Change callback in sortable


Hello.
In Internet there are a lot of samples of code where using serialize
(or toArray) method of sortable to save order of elements in the
database. But I want do not pass all of items and their order to the
server script, I want to give it only two params (in change callback):
item i dragging and item that swapping with dragging item. But in
callback i can olny give my dragging item. How can I to do it?