The 'focus' documentation from <http://jqueryui.com/demos/autocomplete/> states : 

> 
> focusType:autocompletefocus Before focus is moved to an item (not
>  selecting), ui.item refers to the focused item. The default action of
>  focus is to replace the text field's value with the value of the
>  focused item, though only if the focus event was triggered by a
>  keyboard interaction. Canceling this event prevents the value from
>  being updated, but does not prevent the menu item from being focused.
> 
> 
> Code examples
> 
> 
> Supply a callback function to handle the focus event as an init
>  option. $( ".selector" ).autocomplete({ focus: function(event, ui)
>  { ... } }); Bind to the focus event by type: autocompletefocus. $(
>  ".selector" ).bind( "autocompletefocus", function(event, ui) { ...
>  });
> 
> 
> 

Using below code sets an attribute called 'mytag' with value 'tester' on all of the autocomplete elements even though I have not selected the elements. Why is the attribute 'focus' not added just when one of the drop downs is focused, instead of being added when page is loaded ?

```
 $("#myDiv").autocomplete({
    source: availableTags,
    focus: function(event, ui) {
        $(".ui-autocomplete li").attr("mytag", "tester");
    }
  });

```