如何在swift中添加scrollView webView和按钮

Question

如何在scrollView webView和按钮内添加？ 我试过这个，它调整了webview的大小，但没有滚动

 let output = webView.stringByEvaluatingJavaScriptFromString("document.body.offsetHeight;")
            let contentHeight = output?.toInt()
            let conHeight:CGFloat = CGFloat(contentHeight!)
            var frame = self.webView.frame
            frame.size = CGSizeMake(self.webView.frame.size.width, conHeight)
            self.webView.frame = frame