From 832223156f9ae7803c4d4e113fe86e5bb799bd2d Mon Sep 17 00:00:00 2001
From: pangxie1991 <chenyao1102@gmail.com>
Date: Wed, 12 Apr 2017 20:04:08 +0800
Subject: [PATCH] =?UTF-8?q?=E7=A9=BA=E5=80=BC=E5=88=A4=E6=96=AD?=
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---
 packages/waterfall/src/directive.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/waterfall/src/directive.js b/packages/waterfall/src/directive.js
index 77f97c407..5edae9d5c 100644
--- a/packages/waterfall/src/directive.js
+++ b/packages/waterfall/src/directive.js
@@ -104,7 +104,8 @@ export default function(type) {
     },
 
     update(el) {
-      el[CONTEXT].scrollEventListener();
+      const context = el[CONTEXT];
+      context.scrollEventListener && context.scrollEventListener();
     },
 
     unbind(el) {