jQuery sortable is hard to use b/c it's easy to drag outside the lines - what should I do?

I'm using the jQuery ui's sortable feature:

http://jqueryui.com/demos/sortable/

Works great as long as the user never drags the handle past the left border of the containing , but in practice this is easy开发者_StackOverflow社区 to do - and even easier on my website, where the sortable handles have a little less whitespace to the left...

Ideas? Thanks!

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I think you're looking for the containment option:

Constrains dragging to within the bounds of the specified element - can be a DOM element, 'parent', 'document', 'window', or a jQuery selector.

Here's a demo: http://jsfiddle.net/andrewwhitaker/ZB5Tm/1/

Notice what happens when you remove the containment option.