From bc4df8451992f4b7bb5d2d1c5ac1a84b2403b253 Mon Sep 17 00:00:00 2001
From: Harrison Healey <harrisonmhealey@gmail.com>
Date: Thu, 9 Nov 2017 16:48:37 -0500
Subject: [PATCH] RN-471/RN-484 Fixed null pointer exceptions caused by
 ScrollViews (#1116)

* RN-471 Fixed null pointer from Swiper scroll view

* RN-484 Added null check to ImagePreview scroll view
---
 app/components/swiper.js                   | 6 ++++--
 app/screens/image_preview/image_preview.js | 9 +++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/app/components/swiper.js b/app/components/swiper.js
index 72142724f..2a5bc6dfc 100644
--- a/app/components/swiper.js
+++ b/app/components/swiper.js
@@ -71,9 +71,11 @@ export default class Swiper extends PureComponent {
         if (this.runOnLayout) {
             if (Platform.OS === 'ios') {
                 setTimeout(() => {
-                    this.scrollView.scrollTo({x: this.props.width * this.state.index, animated: false});
+                    if (this.scrollView) {
+                        this.scrollView.scrollTo({x: this.props.width * this.state.index, animated: false});
+                    }
                 }, 100);
-            } else {
+            } else if (this.scrollView) {
                 this.scrollView.setPageWithoutAnimation(this.state.index);
             }
             this.runOnLayout = false;
diff --git a/app/screens/image_preview/image_preview.js b/app/screens/image_preview/image_preview.js
index fbe370d36..aa8333925 100644
--- a/app/screens/image_preview/image_preview.js
+++ b/app/screens/image_preview/image_preview.js
@@ -91,7 +91,10 @@ export default class ImagePreview extends PureComponent {
 
     componentDidMount() {
         InteractionManager.runAfterInteractions(() => {
-            this.scrollView.scrollTo({x: (this.state.currentFile) * this.props.deviceWidth, animated: false});
+            if (this.scrollView) {
+                this.scrollView.scrollTo({x: (this.state.currentFile) * this.props.deviceWidth, animated: false});
+            }
+
             Animated.timing(this.state.wrapperViewOpacity, {
                 toValue: 1,
                 duration: 100
@@ -102,7 +105,9 @@ export default class ImagePreview extends PureComponent {
     componentWillReceiveProps(nextProps) {
         if (this.props.deviceWidth !== nextProps.deviceWidth) {
             InteractionManager.runAfterInteractions(() => {
-                this.scrollView.scrollTo({x: (this.state.currentFile * nextProps.deviceWidth), animated: false});
+                if (this.scrollView) {
+                    this.scrollView.scrollTo({x: (this.state.currentFile * nextProps.deviceWidth), animated: false});
+                }
             });
         }