Question

I have a draggable element and I would like to call PHP function each time the element is dropped (basically to save its position – pixels from top and left to mysql database). How to approach it? AJAX?

Answer 1

$("#droppable").droppable({
    drop: function() {
        $.get('http://mysite.com/dragged.php?droppedID='+this.id);
    }
});

EDIT

If you want the id of the draggable (and not what it was dropped on), you need to use the ui parameter when you setup the drop callback:

$( "#draggable" ).draggable();
$("#droppable").droppable({
    drop: function(event, ui) {
        $.get('http://mysite.com/dragged.php?droppedID='+ui.draggable.attr('id'));
    }
});