reject invalid sortable item in a sortable list

Question

I tried many things but not successful :( I have two sortable lists connected with each other. The thing is list 'A' can accept any list item in it. But list 'B' can only accept an item having class = 'abc'

The code is as

<ul id='A'>
  <li>item A1</i>
  <li>item A2</i>
  <li class='abc'>item A3</i>
</ul>

<ul id='B'>
  <li class='abc'>item A1</i>
</ul>

The jquery code I am trying is

$('#A').sortable({revert: true, connectWith: '#B'})
$('#B').sortable({revert: true, connectWith: '#A', over: function(event, ui){
   if(!ui.item.hasClass('abc')){
     ui.placeholder.addClass('ui-state-error');
     ui.sender.sortable('cancel');
   }
}})

Please guide me where I am wrong, thanks

Answer 1

You could try using the receive event instead, although it's a bit delayed doing this and the addClass doesnt work:

$('#A').sortable({revert: true, connectWith: '#B'})
$('#B').sortable({revert: true, connectWith: '#A',
    receive: function(event, ui){
        if(!ui.item.hasClass('abc')){   
            $(ui.placeholder).addClass('ui-state-error');                    
            $(ui.sender).sortable('cancel');
        }}
})​;​

Example - http://jsfiddle.net/b5ykK/1/