From 3541fb188b5294e3cfc04b94982bb8a5d0040b21 Mon Sep 17 00:00:00 2001
From: vishtree <vishalnarkhede.iitd@gmail.com>
Date: Thu, 8 Apr 2021 16:32:18 +0200
Subject: [PATCH] Fixed some logic around enabling mvcp

---
 .../MvcpScrollViewManagerModule.java          | 29 +++++++++++--------
 src/FlatList.android.tsx                      |  7 ++---
 2 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/android/src/main/java/com/mvcpscrollviewmanager/MvcpScrollViewManagerModule.java b/android/src/main/java/com/mvcpscrollviewmanager/MvcpScrollViewManagerModule.java
index fa0ec8e..56b6842 100644
--- a/android/src/main/java/com/mvcpscrollviewmanager/MvcpScrollViewManagerModule.java
+++ b/android/src/main/java/com/mvcpscrollviewmanager/MvcpScrollViewManagerModule.java
@@ -58,19 +58,24 @@ public void run() {
           final UIManagerModuleListener uiManagerModuleListener = new UIManagerModuleListener() {
             @Override
             public void willDispatchViewUpdates(final UIManagerModule uiManagerModule) {
-              ReactViewGroup mContentView = (ReactViewGroup)scrollView.getChildAt(0);
-              if (mContentView == null) return;
-
-              ScrollViewUIHolders.currentScrollY = scrollView.getScrollY();
-
-              for (int ii = minIndexForVisible; ii < mContentView.getChildCount(); ++ii) {
-                View subview = mContentView.getChildAt(ii);
-                if (subview.getTop() >= ScrollViewUIHolders.currentScrollY) {
-                  ScrollViewUIHolders.prevFirstVisibleTop = subview.getTop();
-                  ScrollViewUIHolders.firstVisibleView = subview;
-                  break;
+              uiManagerModule.prependUIBlock(new UIBlock() {
+                @Override
+                public void execute(NativeViewHierarchyManager nativeViewHierarchyManager) {
+                  ReactViewGroup mContentView = (ReactViewGroup)scrollView.getChildAt(0);
+                  if (mContentView == null) return;
+
+                  ScrollViewUIHolders.currentScrollY = scrollView.getScrollY();
+
+                  for (int ii = minIndexForVisible; ii < mContentView.getChildCount(); ++ii) {
+                    View subview = mContentView.getChildAt(ii);
+                    if (subview.getTop() >= ScrollViewUIHolders.currentScrollY) {
+                      ScrollViewUIHolders.prevFirstVisibleTop = subview.getTop();
+                      ScrollViewUIHolders.firstVisibleView = subview;
+                      break;
+                    }
+                  }
                 }
-              }
+              });
             }
           };
 
diff --git a/src/FlatList.android.tsx b/src/FlatList.android.tsx
index 299d328..3f2f81e 100644
--- a/src/FlatList.android.tsx
+++ b/src/FlatList.android.tsx
@@ -23,11 +23,9 @@ export default (React.forwardRef(
     const propAutoscrollToTopThreshold =
       mvcp?.autoscrollToTopThreshold || -Number.MAX_SAFE_INTEGER;
     const propMinIndexForVisible = mvcp?.minIndexForVisible || 1;
-
     const hasMvcpChanged =
       autoscrollToTopThreshold.current !== propAutoscrollToTopThreshold ||
       minIndexForVisible.current !== propMinIndexForVisible;
-
     const enableMvcp = () => {
       if (!flRef.current) return;
 
@@ -45,9 +43,6 @@ export default (React.forwardRef(
     };
 
     const enableMvcpWithRetries = () => {
-      autoscrollToTopThreshold.current = propAutoscrollToTopThreshold;
-      minIndexForVisible.current = propMinIndexForVisible;
-
       return enableMvcp()?.catch(() => {
         /**
          * enableMaintainVisibleContentPosition from native module may throw IllegalViewOperationException,
@@ -86,6 +81,8 @@ export default (React.forwardRef(
       if (isMvcpEnabled.current && !hasMvcpChanged) {
         return;
       }
+      autoscrollToTopThreshold.current = propAutoscrollToTopThreshold;
+      minIndexForVisible.current = propMinIndexForVisible;
 
       isMvcpEnabled.current = true;
       disableMvcp().then(enableMvcpWithRetries);