From a31766326821a8b0d78f7b7f49d1a7288003f49f Mon Sep 17 00:00:00 2001
From: Simon Jackson <sjackson@ethar.com>
Date: Sat, 24 Dec 2022 12:44:23 +0000
Subject: [PATCH] Added error handling around setting Unity UI Components for
 Vertical/Horizontal scrolling

Resolves: https://github.com/Unity-UI-Extensions/com.unity.uiextensions/issues/296
---
 Runtime/Scripts/Layout/HorizontalScrollSnap.cs | 10 +++++++++-
 Runtime/Scripts/Layout/VerticalScrollSnap.cs   |  8 +++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/Runtime/Scripts/Layout/HorizontalScrollSnap.cs b/Runtime/Scripts/Layout/HorizontalScrollSnap.cs
index f6de775..365c1a9 100644
--- a/Runtime/Scripts/Layout/HorizontalScrollSnap.cs
+++ b/Runtime/Scripts/Layout/HorizontalScrollSnap.cs
@@ -114,12 +114,20 @@ namespace UnityEngine.UI.Extensions
         /// <param name="WorldPositionStays">Should the world position be updated to it's parent transform?</param>
         public void AddChild(GameObject GO, bool WorldPositionStays)
         {
-            _scroll_rect.horizontalNormalizedPosition = 0;
+            try
+            {
+                // Rare instances of Unity bug cause error, adding try to manage it.
+                _scroll_rect.horizontalNormalizedPosition = 0;
+            }
+            catch { }
+
             GO.transform.SetParent(_screensContainer, WorldPositionStays);
             InitialiseChildObjectsFromScene();
             DistributePages();
             if (MaskArea)
+            {
                 UpdateVisible();
+            }
 
             SetScrollContainerPosition();
         }
diff --git a/Runtime/Scripts/Layout/VerticalScrollSnap.cs b/Runtime/Scripts/Layout/VerticalScrollSnap.cs
index 58bde93..4493d8b 100644
--- a/Runtime/Scripts/Layout/VerticalScrollSnap.cs
+++ b/Runtime/Scripts/Layout/VerticalScrollSnap.cs
@@ -114,7 +114,13 @@ namespace UnityEngine.UI.Extensions
         /// <param name="WorldPositionStays">Should the world position be updated to it's parent transform?</param>
         public void AddChild(GameObject GO, bool WorldPositionStays)
         {
-            _scroll_rect.verticalNormalizedPosition = 0;
+            try
+            {
+                // Rare instances of Unity bug cause error, adding try to manage it.
+                _scroll_rect.verticalNormalizedPosition = 0;
+            }
+            catch { }
+
             GO.transform.SetParent(_screensContainer, WorldPositionStays);
             InitialiseChildObjectsFromScene();
             DistributePages();