From 25e94d9d7f86f9d9ad457bb9a7cb7f8cd97a0f17 Mon Sep 17 00:00:00 2001
From: Doug <6060466+pixlwave@users.noreply.github.com>
Date: Fri, 12 Apr 2024 10:45:29 +0100
Subject: [PATCH] Fix a bug where the view state is being modified during an
 update. (#2686)

---
 .../Other/SwiftUI/Layout/FullscreenDialog.swift | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/ElementX/Sources/Other/SwiftUI/Layout/FullscreenDialog.swift b/ElementX/Sources/Other/SwiftUI/Layout/FullscreenDialog.swift
index 3649ea933..3d33b48b0 100644
--- a/ElementX/Sources/Other/SwiftUI/Layout/FullscreenDialog.swift
+++ b/ElementX/Sources/Other/SwiftUI/Layout/FullscreenDialog.swift
@@ -135,12 +135,21 @@ struct FullscreenDialog<Content: View, BottomContent: View>: View {
     
     func updateBackgroundVisibility(scrollView: UIScrollView) {
         guard dynamicTypeSize < .accessibility1 else {
-            showsBackground = true
+            if !showsBackground {
+                showsBackground = true
+            }
             return
         }
-        let insetHeight = scrollView.adjustedContentInset.top + scrollView.adjustedContentInset.bottom
-        let availableHeight = scrollView.frame.height - insetHeight
-        showsBackground = scrollView.contentSize.height < availableHeight
+        
+        DispatchQueue.main.async { // Don't modify the state during a view update.
+            let insetHeight = scrollView.adjustedContentInset.top + scrollView.adjustedContentInset.bottom
+            let availableHeight = scrollView.frame.height - insetHeight
+            let shouldShowBackground = scrollView.contentSize.height < availableHeight
+            
+            if showsBackground != shouldShowBackground {
+                showsBackground = shouldShowBackground
+            }
+        }
     }
 }