A PHP Error was encountered

Severity: Notice

Message: Trying to get property of non-object

Filename: controllers/Material.php

Line Number: 123

Backtrace:

File: /home/hosting_users/gngnet_ohou/www/application/controllers/Material.php
Line: 123
Function: _error_handler

File: /home/hosting_users/gngnet_ohou/www/application/controllers/Material.php
Line: 18
Function: call_user_func_array

File: /home/hosting_users/gngnet_ohou/www/index.php
Line: 319
Function: require_once