Q:

Find elements dropped onto other element

I am writing a little application to drop elements onto a bigger block (sort of a canvas).
When I'm done, I click on a button to see which blocks were dropped onto the bigger block. However, if I just look for the id's of the dropped elements, I don't get any results:
var $children = $( "#droppable" ).find('div');
for(i=0; i< $children.length; i++) {
    var $input = $children.eq(i);
    alert(($input).attr('id'));
}

How can I find out which elements were dropped onto the canvas?

A:

I figured out how it is done. I made two drop-areas to which the blocks can be dragged. To make sure that after placing back a block, the CSS positioning doesn't make the draggable 'disappear', I remove the positioning code:
$( "#source" ).droppable({
    drop: function(event, ui) {
        var $draggable = $(ui.draggable).detach();
        $draggable.css({'left':'','top':'','right':'','bottom':''}) ;
        $draggable.prependTo($(this));
    }
});
$( "#destination" ).droppable({
    drop: function(event, ui) {
        var $draggable = $(ui.draggable).detach();
        $draggable.prependTo($(this));
    }
});

