How to fade the content of cell of table view which reaches at the top while scrolling?

Hi everyone i need to implement this functionality.I need to fade the content of the cell while its going to disappear, i mean while it reaches at the top of table view.I am not getting how to do that.Please help me.I tried to use the scrollview's method but not getting how to do that.

- (void)scrollViewDidScroll:(UIScrollView *)scrollView