Warning once only: Detected a case where constraints ambiguously suggest a height of zero for a tableview cell‘s content view. We‘re considering the collapse unintentional and using standard height instead.
遇到以上错误, 添加以下代码可以解决:
self.tableView.rowHeight = 44.0f;
原文：http://www.cnblogs.com/Rinpe/p/5063929.html