jQuery UI Sortable, how to determine current location and new location in update event?

Question

I have:

     
item 1
     
item 2
     
item 3

         


        

Answer 1

This works for me,

$('#app').sortable({
    handle: '.handle',

    start: function(evt, ui){
        $(ui.item).data('old-ndex' , ui.item.index());
    },

    update: function(evt, ui) {
        var old_index = $(ui.item).data('old-ndex');
        var new_index = ui.item.index();

        alert('old_index -'+old_index+' new index -'+new_index);

    }
});