From 91f920ed7efc3850c5bcaa6e6afd2e12d0a05f12 Mon Sep 17 00:00:00 2001
From: Dennis Falling <dennis@culpeos.com>
Date: Fri, 12 Jun 2026 23:16:57 +0100
Subject: [PATCH] Speed up screen transitions and fix local builds on JDK 25
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Stack transitions felt sluggish: react-native-screens hardcodes Android
slide animations to config_mediumAnimTime (400ms) and ignores
react-navigation's animationDuration on Android. Override the four
rns_slide_* anim resources in the app module (resource merging beats the
library's copies) to run at 150ms.

Also fix `bun run android` failing at configureCMake on JDK 25: AGP's
forked prefab CLI triggers the JEP 472 restricted-method warning via JNA,
and AGP treats any unrecognized prefab stderr as fatal. Set
JAVA_TOOL_OPTIONS=--enable-native-access=ALL-UNNAMED in mise.toml's [env]
— AGP whitelists the resulting "Picked up" line — until the upstream fix
(b/469503601) ships in an AGP release.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 android/app/src/main/res/anim/rns_slide_in_from_left.xml | 6 ++++++
 .../app/src/main/res/anim/rns_slide_in_from_right.xml    | 9 +++++++++
 android/app/src/main/res/anim/rns_slide_out_to_left.xml  | 6 ++++++
 android/app/src/main/res/anim/rns_slide_out_to_right.xml | 6 ++++++
 mise.toml                                                | 9 +++++++++
 src/navigation/RootNavigator.tsx                         | 4 ++++
 6 files changed, 40 insertions(+)
 create mode 100644 android/app/src/main/res/anim/rns_slide_in_from_left.xml
 create mode 100644 android/app/src/main/res/anim/rns_slide_in_from_right.xml
 create mode 100644 android/app/src/main/res/anim/rns_slide_out_to_left.xml
 create mode 100644 android/app/src/main/res/anim/rns_slide_out_to_right.xml

diff --git a/android/app/src/main/res/anim/rns_slide_in_from_left.xml b/android/app/src/main/res/anim/rns_slide_in_from_left.xml
new file mode 100644
index 0000000..aaba142
--- /dev/null
+++ b/android/app/src/main/res/anim/rns_slide_in_from_left.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- See rns_slide_in_from_right.xml — keep all four rns_slide_* durations in sync. -->
+<translate xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="150"
+    android:fromXDelta="-100%"
+    android:toXDelta="0%" />
diff --git a/android/app/src/main/res/anim/rns_slide_in_from_right.xml b/android/app/src/main/res/anim/rns_slide_in_from_right.xml
new file mode 100644
index 0000000..39c5554
--- /dev/null
+++ b/android/app/src/main/res/anim/rns_slide_in_from_right.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Overrides react-native-screens' slide animation (400ms config_mediumAnimTime).
+     The animationDuration screen option is a no-op on Android, so app-level
+     resource merging is the only way to change the stack transition speed.
+     Keep all four rns_slide_* durations in sync. -->
+<translate xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="150"
+    android:fromXDelta="100%"
+    android:toXDelta="0%" />
diff --git a/android/app/src/main/res/anim/rns_slide_out_to_left.xml b/android/app/src/main/res/anim/rns_slide_out_to_left.xml
new file mode 100644
index 0000000..dc79333
--- /dev/null
+++ b/android/app/src/main/res/anim/rns_slide_out_to_left.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- See rns_slide_in_from_right.xml — keep all four rns_slide_* durations in sync. -->
+<translate xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="150"
+    android:fromXDelta="0%"
+    android:toXDelta="-100%"/>
diff --git a/android/app/src/main/res/anim/rns_slide_out_to_right.xml b/android/app/src/main/res/anim/rns_slide_out_to_right.xml
new file mode 100644
index 0000000..5ea49b2
--- /dev/null
+++ b/android/app/src/main/res/anim/rns_slide_out_to_right.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- See rns_slide_in_from_right.xml — keep all four rns_slide_* durations in sync. -->
+<translate xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="150"
+    android:fromXDelta="0%"
+    android:toXDelta="100%"/>
diff --git a/mise.toml b/mise.toml
index 391ce89..89fa444 100644
--- a/mise.toml
+++ b/mise.toml
@@ -9,3 +9,12 @@
 node = "24"
 bun = "1.3.14"
 java = "temurin-25.0.3+9.0.LTS"
+
+[env]
+# On JDK 24+ the JVM warns on stderr when JNA calls System::load (JEP 472).
+# AGP forks the prefab CLI during configureCMake* and fails the build on any
+# unrecognized stderr line, so the warning breaks `bun run android`. AGP does
+# whitelist the "Picked up JAVA_TOOL_OPTIONS" line, making this env var the
+# supported way to grant native access in forked JVMs until the AGP fix
+# (issuetracker b/469503601) ships in a release.
+JAVA_TOOL_OPTIONS = "--enable-native-access=ALL-UNNAMED"
diff --git a/src/navigation/RootNavigator.tsx b/src/navigation/RootNavigator.tsx
index a66d4fe..f721a72 100644
--- a/src/navigation/RootNavigator.tsx
+++ b/src/navigation/RootNavigator.tsx
@@ -11,6 +11,10 @@ const Stack = createNativeStackNavigator<RootStackParamList>();
  * The authenticated app's screen stack. Headers are hidden — each screen draws
  * its own chrome edge-to-edge and applies its own safe-area padding. The detail
  * screen slides in from the right as a standard forward push.
+ *
+ * Transition speed: react-navigation's `animationDuration` option is a no-op on
+ * Android, so the slide duration is set by overriding react-native-screens'
+ * anim resources in android/app/src/main/res/anim/rns_slide_*.xml.
  */
 export function RootNavigator() {
   return (