crash - Please help

I am a new roku developer...I have implemented roListScreen(containing channels as list items) which is working fine...among all the list items, i have implemented roposterscreen for the first list item only and not for any other list items...if i am clicking on any other list item the program is crashed and not able to operate anything using the roku remote....

I donno whether this problem is because of the program code or the roku device....

Please help me in solving this...