uitableView固定某一控件

- (void)scrollViewDidScroll:(UIScrollView *)scrollView{    NSLog(@"%f",self.tableView.contentOffset.y);    CGFloat height = self.tableView.contentOffset.y;    if (height >= 283.0) {        [self.menuDrop removeFromSuperview];        self.menuDrop.frame = CGRectMake(0, 64, width(self.tableView.frame), kHeight_menu);        self.appdelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;        [self.appdelegate.window addSubview:self.menuDrop];    }else {        [self.menuDrop removeFromSuperview];        self.menuDrop.frame = CGRectMake(0, maxY(self.advertView) - kHeight_menu + 1*KScDefineWidth, width(self.tableView.frame), kHeight_menu);        [self.tableView addSubview:self.menuDrop];    }}