List View Change Selection old value - new value

Hi,
I need after changing the selection in a list view the new and old (previously selected) id of the selected entry.
Using
$$(“list_projekte”).attachEvent(“onAfterSelect”, function (id) {
alert("selected id: "+id)
});
I just get the new value…
Is there a way achieving this?

Thanks,
Martin

Anybody could help me with this?

Thanks,
Martin

You can use the onBeforeSelect event:

http://webix.com/snippet/e1e6d653