$('.draggable').draggable({
revert: "invalid",
stack: ".draggable",
helper: 'clone'
});
$('.droppable').droppable({
accept: ".draggable",
drop: function(event, ui) {
var droppable = $(this);
var draggable = ui.draggable;
// Move draggable into droppable
var drag = $('.droppable').has(ui.draggable).length ? draggable : draggable.clone().draggable({
revert: "invalid",
stack: ".draggable",
helper: 'clone'
});
drag.appendTo(droppable);
draggable.css({
float: 'left'
});
}
});