去掉UItableview headerview黏性

 //去掉UItableview headerview黏性
 - (void)scrollViewDidScroll:(UIScrollView *)scrollView {
     if (scrollView == self.tableView)
     {
         CGFloat sectionHeaderHeight = ;
         if (scrollView.contentOffset.y<=sectionHeaderHeight&&scrollView.contentOffset.y>=) {
             scrollView.contentInset = UIEdgeInsetsMake(-scrollView.contentOffset.y, , , );
         } else if (scrollView.contentOffset.y>=sectionHeaderHeight) {
             scrollView.contentInset = UIEdgeInsetsMake(-sectionHeaderHeight, , , );
         }
     }
 }