From 5eac8ca9b05230b32a101db5336b1c996b97312e Mon Sep 17 00:00:00 2001
From: David Vacca <dvacca@fb.com>
Date: Tue, 30 Apr 2019 15:01:40 -0700
Subject: [PATCH] Migrate VirtualizedList to use ref.measureLayout

Summary: This diff migrates VirtualizedList to use ref.measureLayout instead of UIManager.measureLayout, this is a pre-req to make measureLayout to work in Fabric

Reviewed By: JoshuaGross, TheSavior

Differential Revision: D14865762

fbshipit-source-id: 45dd3374813370188c914acfc7e631075508f74a
---
 Libraries/Components/ScrollView/ScrollView.js |  4 +++
 Libraries/Lists/VirtualizedList.js            | 33 ++++++++++++++-----
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/Libraries/Components/ScrollView/ScrollView.js b/Libraries/Components/ScrollView/ScrollView.js
index 37e951edb..a912662e6 100644
--- a/Libraries/Components/ScrollView/ScrollView.js
+++ b/Libraries/Components/ScrollView/ScrollView.js
@@ -730,6 +730,10 @@ class ScrollView extends React.Component<Props, State> {
     return ReactNative.findNodeHandle(this._innerViewRef);
   }
 
+  getNativeScrollRef(): ?ScrollView {
+    return this._scrollViewRef;
+  }
+
   /**
    * Scrolls to a given x, y offset, either immediately or with a smooth animation.
    *
diff --git a/Libraries/Lists/VirtualizedList.js b/Libraries/Lists/VirtualizedList.js
index 573eb8c22..95ff01cfb 100644
--- a/Libraries/Lists/VirtualizedList.js
+++ b/Libraries/Lists/VirtualizedList.js
@@ -413,6 +413,14 @@ class VirtualizedList extends React.PureComponent<Props, State> {
     }
   }
 
+  getScrollRef() {
+    if (this._scrollRef && this._scrollRef.getScrollRef) {
+      return this._scrollRef.getScrollRef();
+    } else {
+      return this._scrollRef;
+    }
+  }
+
   setNativeProps(props: Object) {
     if (this._scrollRef) {
       this._scrollRef.setNativeProps(props);
@@ -1124,17 +1132,18 @@ class VirtualizedList extends React.PureComponent<Props, State> {
     // TODO (T35574538): findNodeHandle sometimes crashes with "Unable to find
     // node on an unmounted component" during scrolling
     try {
-      UIManager.measureLayout(
-        ReactNative.findNodeHandle(this),
+      if (!this._scrollRef) {
+        return;
+      }
+      // We are asuming that getOutermostParentListRef().getScrollRef()
+      // is a non-null reference to a ScrollView
+      this._scrollRef.measureLayout(
         ReactNative.findNodeHandle(
-          this.context.virtualizedList.getOutermostParentListRef(),
+          this.context.virtualizedList
+            .getOutermostParentListRef()
+            .getScrollRef()
+            .getNativeScrollRef(),
         ),
-        error => {
-          console.warn(
-            "VirtualizedList: Encountered an error while measuring a list's" +
-              ' offset from its containing VirtualizedList.',
-          );
-        },
         (x, y, width, height) => {
           this._offsetFromParentVirtualizedList = this._selectOffset({x, y});
           this._scrollMetrics.contentLength = this._selectLength({
@@ -1148,6 +1157,12 @@ class VirtualizedList extends React.PureComponent<Props, State> {
           this._scrollMetrics.visibleLength = scrollMetrics.visibleLength;
           this._scrollMetrics.offset = scrollMetrics.offset;
         },
+        error => {
+          console.warn(
+            "VirtualizedList: Encountered an error while measuring a list's" +
+              ' offset from its containing VirtualizedList.',
+          );
+        },
       );
     } catch (error) {
       console.warn(