function addcat($id=null) {
        $this->layout='ajax';
        $id=$_GET['id'];

$id     =       null

HomeController::addcat() - APP/controllers/home_controller.php, line 82
Dispatcher::_invoke() - CORE/cake/dispatcher.php, line 204
Dispatcher::dispatch() - CORE/cake/dispatcher.php, line 171
[main] - APP/webroot/index.php, line 83