去掉TableView的粘性（转）

section的headerview或者footerview会黏在屏幕的顶端或者下端，不会跟着tableview一起整体滚动

- (void)scrollViewDidScroll:(UIScrollView *)sender {

  if(sender == _myTab) {

      CGFloat sectionHeaderHeight = 30;

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

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

     } else if (sender.contentOffset.y>=sectionHeaderHeight) {

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

    }

  }

}