去掉UItableview headerview黏性(sticky)

// 去掉UItableview headerview黏性(sticky)
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat sectionHeaderHeight = 40;
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);
}
}