let dealsSeeMoreViewController = DealsSeeMoreViewController(owner: self)
self.dealsStackView.addArrangedSubview(dealsSeeMoreViewController.view)
只写上面两句的话，dealsSeeMoreViewController可能已经被释放，所以view里面的点击事件会不响应。
要把dealsSeeMoreViewController加进来，如下：
self.addChildViewController(dealsSeeMoreViewController)
dealsSeeMoreViewController.didMoveToParentViewController(self)