have folder for diferent users

i have tried to have diferent folder for diferent users , so each user will have his own folder and he will be able to see just the files on his folder.

my idea is to put the docs on the images folder under the folder with the username, i tried to do this

add this code on the helper.php

$user = &JFactory::getUser(); //to get username

function getFormattedListing($params)

{

//specify the folder

$folder = (“images/”.$user->username);

$list = array();

$result = “”;

but the proble is it is just calling the images folder and it isn’t getting the the username i have tested to echo the username on the default.php and it worked so i don’t know why it isn’t working on helper.php

i will be glad if you could help me , i have looked on the joomla extension and i didn’t anything that would suit, your is the nearst of what i want.