取消scrollView上下拉升

    if (ios_Vewsion_5_Or_Above) {

        _scrollView.bounces = NO;

    } else {

        for (id subview in _scrollView.subviews)

            if ([[subview class] isSubclassOfClass: [UIScrollView class]])

                ((UIScrollView *)subview).bounces = NO;

    }