gistfile1.m

// dataArray is the nsdictionary/array containing you list of names; we take the 1st letter of each, and compare it with the title of the Index the user "clicked" on
// we cycle through all your names until we find a name starting with the letter that he touched in the index. When we found the name, we scroll the table tot that row.
 
- (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index {
    for (int i = 0; i< [dataArray count]; i++) {
        NSString *letterString = [[dataArray objectAtIndex:i] substringToIndex:1];
        if ([letterString isEqualToString:title]) {
            [tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:YES];
            break;
        }
    }
}