JQuery - How can I conditionally cancel drop while hovering over a droppable?
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I have a setup where I want to conditionally revert an element that is being dropped

(I tried using the 'accept' event, but that proved to run far too often for practical purposes. - not only that, its use cancels other events.)

TO illustrate my intention, I have an example using accept: http://jsfiddle.net/KevinGabbert/rUwgc/14/

The problem is, using that method.. over() does not fire.  instead, accept() does in its place - and it fires way too often for my needs.

For example above:

1. grab a piece, and drop it on an unoccupied square (it will revert)
2. click 'Toggle droppability' and try to set on unoccupied square (the piece will now set on the square)

**What I am trying to do is to conditionally "toggle droppability", but while hovering over an element.**

The reason is, as you will see with my example, being squares with chess pieces, depending on what square a piece is over at a particular point in time., I might not want to allow a drop.  Other times, I would want to.

