fix expo-scroll-edge-effect not finding the scrollview

2026-06-26 17:26:57 +02:00
parent 870d899ab2
commit e9b81b303a
4 changed files with 134 additions and 0 deletions
@@ -0,0 +1,88 @@
+diff --git a/ios/ExpoScrollEdgeEffectView.swift b/ios/ExpoScrollEdgeEffectView.swift
+index 44b03cc7c33e770585e232635b7db2dfd21aee8b..6b24e55cf97c96142e53172dc9097c4e054d4d53 100644
+--- a/ios/ExpoScrollEdgeEffectView.swift
+++ b/ios/ExpoScrollEdgeEffectView.swift
+@@ -4,10 +4,14 @@ import UIKit
+ class ExpoScrollEdgeEffectView: ExpoView {
+   private var currentInteraction: NSObject?
+ 
+  private var isAttached = false
+  private var resolveAttempts = 0
+  private let maxResolveAttempts = 30
+
+   var scrollViewTag: Int? {
+     didSet {
+       if scrollViewTag != oldValue {
+-        updateInteraction()
+        scheduleResolve()
+       }
+     }
+   }
+@@ -15,7 +19,7 @@ class ExpoScrollEdgeEffectView: ExpoView {
+   var edge: String = "top" {
+     didSet {
+       if edge != oldValue {
+-        updateInteraction()
+        scheduleResolve()
+       }
+     }
+   }
+@@ -23,7 +27,7 @@ class ExpoScrollEdgeEffectView: ExpoView {
+   var effect: String = "automatic" {
+     didSet {
+       if effect != oldValue {
+-        updateInteraction()
+        scheduleResolve()
+       }
+     }
+   }
+@@ -42,17 +46,39 @@ class ExpoScrollEdgeEffectView: ExpoView {
+   override func didMoveToWindow() {
+     super.didMoveToWindow()
+     if window != nil {
+      scheduleResolve()
+    }
+  }
+
+  override func layoutSubviews() {
+    super.layoutSubviews()
+
+    if !isAttached, window != nil, scrollViewTag != nil, resolveAttempts < maxResolveAttempts {
+       updateInteraction()
+     }
+   }
+ 
+  private func scheduleResolve() {
+    resolveAttempts = 0
+    updateInteraction()
+  }
+
+   private func updateInteraction() {
+     removeInteraction()
+ 
+     guard window != nil else { return }
+     guard let tag = scrollViewTag else { return }
+     guard #available(iOS 26, *) else { return }
+-    guard let scrollView = resolveScrollView(tag: tag) else { return }
+    guard let scrollView = resolveScrollView(tag: tag) else {
+      if resolveAttempts < maxResolveAttempts {
+        resolveAttempts += 1
+        setNeedsLayout()
+      }
+      return
+    }
+
+    resolveAttempts = 0
+    isAttached = true
+ 
+     let resolvedEdge = self.resolveEdge(edge)
+     let resolvedStyle = self.resolveEffectStyle(effect)
+@@ -79,6 +105,8 @@ class ExpoScrollEdgeEffectView: ExpoView {
+   }
+ 
+   private func removeInteraction() {
+    isAttached = false
+
+     guard #available(iOS 26, *) else { return }
+ 
+     if let interaction = currentInteraction as? UIScrollEdgeElementContainerInteraction {
@@ -0,0 +1,44 @@
+# @bsky.app\_\_expo-scroll-edge-effect.patch
+
+Fixes the iOS 26 scroll edge effect (the blur under the status bar) failing to
+attach on the New Architecture (Fabric).
+
+## Why
+
+The native view resolves the target scroll view by React tag:
+`scrollViewTag` (published from JS when the scroll view mounts) ->
+`appContext.findView(withTag:)` -> attach a `UIScrollEdgeElementContainerInteraction`.
+
+On Paper this resolved on the first try, because view-by-tag registration was
+serialized through the single UIManager batch pipeline - by the time the tag
+prop reached native, the scroll view was already in the registry.
+
+On Fabric there is no synchronous tag->view registry. The scroll view's
+`ComponentView` is registered when its mount transaction is applied, which is
+deferred relative to the JS commit that set the tag. So the one-shot
+`resolveScrollView` runs before the view is mounted and returns nil, the
+interaction never attaches, and the blur is lost. (The un-gated case happened to
+work only because the header's `didMoveToWindow` provided a late second attempt;
+a list mounted later - e.g. behind an `isActive` gate - had no such retry.)
+
+## What it does
+
+Makes resolution event-driven and self-healing instead of one-shot:
+
+- When `resolveScrollView` returns nil, it bumps a bounded counter and calls
+  `setNeedsLayout()`; `layoutSubviews()` re-attempts as sibling views mount, so
+  it retries exactly when the scroll view actually appears - no fixed timer.
+- `isAttached` stops re-running once resolved (no teardown/re-attach churn).
+- `resolveAttempts` / `maxResolveAttempts` bound the retries so a
+  permanently-absent scroll view (list not rendered) cannot spin layout forever.
+- The budget is reset on every "fresh" trigger (prop change, entering the
+  window) via `scheduleResolve()`, so each new tag gets a full retry budget.
+
+## Notes
+
+- iOS only; gated behind `#available(iOS 26, *)`.
+- This mirrors how `react-native-screens` handles the same effect on Fabric
+  (resolve from the live view hierarchy and re-apply on mount/layout lifecycle
+  rather than a single tag lookup). A cleaner long-term fix would move
+  resolution to the scroll-view side, but this is the minimal change to the
+  existing tag-based design.
@@ -215,6 +215,7 @@ overrides:
  react-native-screens: 4.24.0

 patchedDependencies:
+  '@bsky.app/expo-scroll-edge-effect': b745392cadb2a707a0b6fcd12de9dc3313765aaf6de089a4a69e6b910a19d724
  '@sentry/react-native@6.20.0': 1d48e4d5178f5684eb33262299e7eed283bf9601f79b9ae1af63a7f607d3483a
  expo-age-range@0.2.18: c325225749993424461eeece1d97a99b19c00da2ebc958a73c12e4eca0c39306
  expo-glass-effect@55.0.8: 6c9fa5b104e53b87df4e17b320acb3b94d12ac90c0101190045dd620681efff0
@@ -19,6 +19,7 @@ allowBuilds:
  'esbuild': true
  'unrs-resolver': true
 patchedDependencies:
+  '@bsky.app/expo-scroll-edge-effect': patches/@bsky.app__expo-scroll-edge-effect.patch
  '@sentry/react-native@6.20.0': patches/@sentry__react-native@6.20.0.patch
  expo-age-range@0.2.18: patches/expo-age-range@0.2.18.patch
  'expo-haptics@15.0.8': patches/expo-haptics@15.0.8.patch