Swap elements when you drag one onto another using jQuery UI

I have an arrangement of elements on a page:

<div>
  <div class="dragdrop" style="top:0px;  left: 0px;  ">1</div>
  <div class="dragdrop" style="top:40px; left: 0px;  ">2</div>
  <div class="dra开发者_如何学Gogdrop" style="top:60px; left: 0px;  ">3</div>
  <div class="dragdrop" style="top:0px;  left: 100px;">4</div>
  <div class="dragdrop" style="top:40px; left: 100px;">5</div>
  <div class="dragdrop" style="top:60px; left: 100px;">6</div>
</div>

How can I use jQuery UI (Draggable / Droppable) to make it so that if one div is dropped onto another, they swap positions? (And if it's dragged anywhere else, it reverts back to its old position.)

Thanks.

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Here is an example of how you can swap elements with drag and drop http://jsfiddle.net/76yRN/1/

Another question about swapping elements in jquery jQuery draggable items lose their draggability after being swapped (with jsfiddle example)

Hope this helps

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You just replace the elements from one to another. Some time ago i have created a demo for swapping elements between to UL list. check this: http://www.authorcode.com/swap-elements-when-drag-one-onto-another-using-jquery-ui/

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I used a combination of solutions to arrive at this, with #large_tiles and #small_tiles being two lists:

$(function() {
$("#large_tiles li, #small_tiles li").draggable({
    zIndex: 2,
    appendTo: "body",
});

initDroppable($("#large_tiles li, #small_tiles li"));

initSwap();
function initSwap() {
    initDroppable($("#large_tiles li, #small_tiles li"));
    initDraggable($("#large_tiles li, #small_tiles li"));
}
function initDraggable($elements) {
    $elements.draggable({
        zIndex: 2,
        appendTo: "body",
        helper: "clone",
        start: function(e, ui) {
            $(ui.helper).addClass("clone");
        },
        cursorAt: { left:50, top:75 }
    });
}
function initDroppable($elements) {
    $elements.droppable({
        activeClass: "active-tile",
        hoverClass: "hover-tile",
        over: function(event, ui) {
            var $this = $(this);
        },
        drop: function(event, ui) {
            var $this = $(this);
            var linew1 = $(this).after(ui.draggable.clone());
            var linew2 = $(ui.draggable).after($(this).clone());
            $(ui.draggable).remove();
            $(this).remove();
            initSwap();
        }
    });
}
});