Multiple Draggable

$(function () {
    gridX = 1; //1 to default
    gridY = 1; //1 to default
    $('#draggable> *').draggable({
        grid: [ grid, gridY ],
        distance: 20,
        containment: '#parent',
        start: function(event, ui) {
            selectedObjs = $('div.ui-selected').filter('[id!='+$(this).attr('id')+']');
            delete startPos;
        },
        drag: function(event, ui) {
            var currentLoc = $(this).position();
            var start = ui.originalPosition;
            var offsetLeft = currentLoc.left-start.left;
            var offsetTop = currentLoc.top-start.top;

            moveSelected(offsetLeft, offsetTop);
        }
    });

    function moveSelected(ol, ot) {
        selectedObjs.each(function() {
            if(typeof(startPos) == 'undefined') {
                startPos =$(this).position();
            }
            $(this).css('left', Math.floor((startPos.left+ol)/gridX)*gridX);
            $(this).css('top', Math.floor((startPos.top+ot)/gridY)*gridY);
        });
    }
}