iOS unity build blackscreen, unmounting on blur, and not properly pausing/resuming when that's fixed

[SethCram]

Today I used patch-package to patch @azesmway/react-native-unity@1.0.11 for the project I'm working on.

Here is the diff that solved my problem:

diff --git a/node_modules/@azesmway/react-native-unity/ios/RNUnityView.mm b/node_modules/@azesmway/react-native-unity/ios/RNUnityView.mm
index a4caa74..46e1a38 100644
--- a/node_modules/@azesmway/react-native-unity/ios/RNUnityView.mm
+++ b/node_modules/@azesmway/react-native-unity/ios/RNUnityView.mm
@@ -84,9 +84,14 @@ static RNUnityView *sharedInstance;
 - (void)layoutSubviews {
    [super layoutSubviews];
 
+   if(![self unityIsInitialized]) {
+      [self initUnityModule];
+   }
+
    if([self unityIsInitialized]) {
       self.ufw.appController.rootView.frame = self.bounds;
       [self addSubview:self.ufw.appController.rootView];
+      [[self ufw] pause:false];
    }
 }
 
@@ -158,14 +163,12 @@ static RNUnityView *sharedInstance;
     [super prepareForRecycle];
 
     if ([self unityIsInitialized]) {
-      [[self ufw] unloadApplication];
-
+      [[self ufw] pause:true];
+      // Keep Unity running when the view is recycled; just detach the view tree.
       NSArray *viewsToRemove = self.subviews;
       for (UIView *v in viewsToRemove) {
           [v removeFromSuperview];
       }
-
-      [self setUfw:nil];
     }
 }
 

I believe the issues were likely caused by the new fabric architecture. When I upgraded the Expo SDK 49 -> 53 I started having these issues.

[ProgrammingW]

@SethCram Amazing, I spent the whole day with this issue and this worked for me, thank you so much!

[steavenb]

Observed a crash in certain cases and with Sentry errors saying

The user or the OS watchdog terminated your app while it blocked the main thread for at least 2000 ms.

I uploaded the stack trace to Claude and it suggested I add a guard to your changes above

if([self unityIsInitialized]) {
      self.ufw.appController.rootView.frame = self.bounds;
      if(self.ufw.appController.rootView.superview != self) {
         [self addSubview:self.ufw.appController.rootView];
      }
      [[self ufw] pause:false];
   }