X and Y Positions of multiple jQuery UI Elements

问题

im trying to collect the positions of multiple draggable elements using jQuery UI.

At the moment I can get the position of one element, but when I move around another, both positions change.

Please can someone assist me in getting the separate positions of multiple draggable items.

http://codepen.io/anon/pen/nLGIl

HTML

<div class="dragThis" id="box-1"style="top: 100px; left: 50px;" >
  <h2>Test 1</h2>
  <p>This is a test</p>
  <ul>
    <li class="posX"></li>
    <li class="posY"></li>
  </ul>
</div>

<div class="dragThis" id="box-1" style="top: 50px; left: 100px;" >
  <h2>Test 2</h2>
  <p>This is a test</p>
  <ul>
    <li class="posX"></li>
    <li class="posY"></li>
  </ul>
</div>

CSS

.dragThis {
    min-width: 50px;
    max-width: 300px;
    min-height: 50px;
    max-height: 400px;
    overflow: auto;
    padding: 10px;

    background: #efefef;
    border: 3px solid #ccc;
    border-radius: 10px;

    display: inline-block;

    position: absolute;
    top: 0px;
    left: 0px;
    z-index: 0;
}

.dragThis h2 {
    font-size: 20px;
    margin: 0;
    padding: 0;
}

.dragThis ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.top {z-index: 2; position: relative}
.bottom {z-index: 1; position: relative}

JS

$(document).ready(function() {
    var a = 3;

    $('.dragThis').draggable(
    {
        start: function(){
            $(this).css("z-index", a++);
        },
        drag: function(){
            var offset = $(this).offset();
            var xPos = offset.left;
            var yPos = offset.top;
            $('.posX').text('x: ' + xPos);
            $('.posY').text('y: ' + yPos);
        }
    });

    $('.dragThis').click(function(){
      $(this).addClass('top').removeClass('bottom');

        $(this).siblings().removeClass('top').addClass('bottom');
        $(this).css("z-index", a++);
    });

});

回答1:

First of all, Double ID's are not good.. box-1 and box-2 are better:

You are matching all elements with class '.posX' etc. Try this:

$(document).ready(function() {
    var a = 3;

    $('.dragThis').draggable(
    {
        start: function(){
            $(this).css("z-index", a++);
        },
        drag: function(){
            var offset = $(this).offset();
            var xPos = offset.left;
            var yPos = offset.top;
            $(this).find('.posX').text('x: ' + xPos);
            $(this).find('.posY').text('y: ' + yPos);
        }
    });

    $('.dragThis').click(function(){
      $(this).addClass('top').removeClass('bottom');

        $(this).siblings().removeClass('top').addClass('bottom');
        $(this).css("z-index", a++);
    });

});

回答2:

$('.posX', this).text('x: ' + xPos);
$('.posY', this).text('y: ' + yPos);

instead of

$('.posX').text('x: ' + xPos);
$('.posY').text('y: ' + yPos);

Sample - http://codepen.io/anon/pen/yKvcB

回答3:

By doing this $('.posX') you've selected ALL elements with this class when you need only those on the active box, so the code would be like this :

$(this).find('.posX').text('x: ' + xPos);
$(this).find('.posY').text('y: ' + yPos);

DEMO : http://codepen.io/anon/pen/FpCtu

来源：https://stackoverflow.com/questions/17293821/x-and-y-positions-of-multiple-jquery-ui-elements