I couldn't find what I'm doing wrong here...
I'm trying to apply some effect on the selected <li> of the navigation, I'm getting the index of it but I can't apply anything on it :
$("#tabs").bind('tabsselect', function(event, ui) {
var choosen = ui.index;
console.log(choosen);
$('#tabs ul').find('li:eq(choosen)').toggleClass('selectedone');
});