tableView组间距

//session头间距

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section

{

    return 20;

}

//去掉session的headerview粘性

- (void)scrollViewDidScroll:(UIScrollView *)scrollView

{

    CGFloat sectionHeaderHeight = 20;

    if (scrollView.contentOffset.y<=sectionHeaderHeight&&scrollView.contentOffset.y>=0) {

        scrollView.contentInset = UIEdgeInsetsMake(-scrollView.contentOffset.y, 0, 0, 0);

    }

    else if (scrollView.contentOffset.y>=sectionHeaderHeight) {

        scrollView.contentInset = UIEdgeInsetsMake(-sectionHeaderHeight, 0, 0, 0);

    }

}