From 0583de7158f7129812d85dfc9416c357aabbe893 Mon Sep 17 00:00:00 2001
From: Djorkaeff Alexandre <djorkaeff.unb@gmail.com>
Date: Wed, 8 Jul 2020 13:36:37 -0300
Subject: [PATCH] [FIX] Scroll to top crashing when ref is undefined (#2252)

---
 app/views/RoomView/index.js      |  2 +-
 app/views/RoomsListView/index.js | 25 ++++++++++---------------
 2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/app/views/RoomView/index.js b/app/views/RoomView/index.js
index 62553d368..bb7fe3e4d 100644
--- a/app/views/RoomView/index.js
+++ b/app/views/RoomView/index.js
@@ -755,7 +755,7 @@ class RoomView extends React.Component {
 			if (handleCommandScroll(event)) {
 				const offset = input === 'UIKeyInputUpArrow' ? 100 : -100;
 				this.offset += offset;
-				this.flatList.scrollToOffset({ offset: this.offset });
+				this.flatList?.scrollToOffset({ offset: this.offset });
 			} else if (handleCommandRoomActions(event)) {
 				this.goRoomActionsView();
 			} else if (handleCommandSearchMessages(event)) {
diff --git a/app/views/RoomsListView/index.js b/app/views/RoomsListView/index.js
index 5b1d396d3..3fd5c7386 100644
--- a/app/views/RoomsListView/index.js
+++ b/app/views/RoomsListView/index.js
@@ -504,12 +504,7 @@ class RoomsListView extends React.Component {
 				closeSearchHeader();
 			}
 			setTimeout(() => {
-				const offset = isAndroid ? 0 : SCROLL_OFFSET;
-				if (this.scroll.scrollTo) {
-					this.scroll.scrollTo({ x: 0, y: offset, animated: true });
-				} else if (this.scroll.scrollToOffset) {
-					this.scroll.scrollToOffset({ offset });
-				}
+				this.scrollToTop();
 			}, 200);
 		});
 	};
@@ -538,9 +533,7 @@ class RoomsListView extends React.Component {
 			search: result,
 			searching: true
 		});
-		if (this.scroll && this.scroll.scrollTo) {
-			this.scroll.scrollTo({ x: 0, y: 0, animated: true });
-		}
+		this.scrollToTop();
 	}, 300);
 
 	getRoomTitle = item => RocketChat.getRoomTitle(item)
@@ -561,15 +554,17 @@ class RoomsListView extends React.Component {
 		this.goRoom({ item, isMasterDetail });
 	};
 
+	scrollToTop = () => {
+		const offset = isAndroid ? 0 : SCROLL_OFFSET;
+		if (this.scroll?.scrollToOffset) {
+			this.scroll.scrollToOffset({ offset });
+		}
+	}
+
 	toggleSort = () => {
 		const { toggleSortDropdown } = this.props;
 
-		const offset = isAndroid ? 0 : SCROLL_OFFSET;
-		if (this.scroll.scrollTo) {
-			this.scroll.scrollTo({ x: 0, y: offset, animated: true });
-		} else if (this.scroll.scrollToOffset) {
-			this.scroll.scrollToOffset({ offset });
-		}
+		this.scrollToTop();
 		setTimeout(() => {
 			toggleSortDropdown();
 		}, 100);