DRAG REFERT

Test Fiddle mainly for SO Questions

by bizamajig

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<div id="droppable" class="ui-widget-header">
    <p>Drop me here</p>
</div>
<div id="origin">
    <div id="draggable" class="ui-widget-content">
        <p>I revert when I'm not dropped</p>
    </div>
</div>

CSS

#draggable, #draggable2 { width: 100px; height: 100px; padding: 0.5em; float: left; margin: 10px 10px 10px 0; }
#droppable { width: 150px; height: 150px; padding: 0.5em; float: left; margin: 10px; }

JavaScript

$(function() {
    $("#draggable").draggable({ 
        revert:  function(dropped) {
             var $draggable = $(this),
                 hasBeenDroppedBefore = $draggable.data('hasBeenDropped'),
                 wasJustDropped = dropped && dropped[0].id == "droppable";
             if(wasJustDropped) {
                 // don't revert, it's in the droppable
                 return false;
             } else {
                 if (hasBeenDroppedBefore) {
                     // don't rely on the built in revert, do it yourself
                     $draggable.animate({ top: 0, left: 0 }, 'slow');
                     return false;
                 } else {
                     // just let the build in work, although really, you could animate to 0,0 here as well
                     return true;
                 }
             }
        }
    });

    $("#droppable").droppable({
        activeClass: 'ui-state-hover',
        hoverClass: 'ui-state-active',
        drop: function(event, ui) {
            $(this).addClass('ui-state-highlight').find('p').html('Dropped!');
            $(ui.draggable).data('hasBeenDropped', true);
        }
    });
});