Problem with a tutorial

1

hello i recently tried out this turorial for the photo gallery … http://www.kirupa.com/developer/mx2004/xml_flash_photogallery.htm … i cannot get the previous button to work for anything … here is the part of the code that ive used for the actionscript that controls the previous … can anyone help? … thanks jm

listen = new Object();
listen.onKeyDown = function() {
if (Key.getCode() == Key.LEFT) {
prevImage();
} else if (Key.getCode() == Key.RIGHT) {
nextImage();
}
};
Key.addListener(listen);
previous_btn.onRelease = function() {
prevImage();
};
next_btn.onRelease = function() {
nextImage();
};