<?php Prado::using('System.Web.UI.ActiveControls.*'); class Issue120 extends TPage { public function buttonClickCallback($sender, $param) { $this -> ddl1 -> setDataSource( array( 'callback value 1' => 'callback item 1', 'callback value 2' => 'callback item 2', 'callback value 3' => 'callback item 3', 'callback value 4' => 'callback item 4' ) ); $this -> ddl1 -> dataBind(); } } ?>