iOS11 MJRefresh PageEnabled 偏移

UITableView 添加一下设置，关键是_tableView.estimatedRowHeight = 0;

if (@available(iOS 11.0, *)) {
        _tableView.estimatedRowHeight = 0;
        _tableView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
    } else {
        self.automaticallyAdjustsScrollViewInsets = NO;
    }

在MJRefreshBackFooter.m中，- (void)scrollViewContentOffsetDidChange:(NSDictionary *)change方法内的if (self.state == MJRefreshStateRefreshing) return;改成

    // 如果正在刷新，直接返回
    if (self.state == MJRefreshStateRefreshing)
    {
        // 修复 pageEnable 造成的偏移
        if (self.scrollView.pagingEnabled == NO) return;
        CGFloat refreshingOffset = [self happenOffsetY] + self.mj_h;
        if (refreshingOffset != self.scrollView.mj_offsetY)
        {
            self.scrollView.mj_offsetY = [self happenOffsetY] + self.mj_h;
        }
        return;
    }