From 9289a322bcb3aa286df1335b6d7a1ffe555346b1 Mon Sep 17 00:00:00 2001
From: "J.T. James" <jt.james@planningcenter.com>
Date: Thu, 9 Jul 2026 15:22:05 -0400
Subject: [PATCH] Discard measured responder region that excludes the grant
 touch
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The responder is granted by a native hit test, so the touch that granted
it necessarily lies inside the view's true on-screen region. When a view
has been repositioned by native code after layout (e.g. a native sheet
footer pinned with AutoLayout), measure() still reports the stale layout
frame; Pressability then cancels the press on the first touchMove
because the touch is outside the measured rect — press feedback fires,
onPress never does. Stationary simulator taps emit no move events, so
the bug only reproduces on physical devices.

Validate the measured region against the grant touch position: if the
region excludes the point where the press was granted, the measurement
is provably stale, so discard it. A null region already means "skip
press-rect checks", and correct measurements are unaffected since they
contain the grant point by construction.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 .../Libraries/Pressability/Pressability.js    | 28 ++++++++
 .../__tests__/Pressability-test.js            | 64 +++++++++++++++++++
 2 files changed, 92 insertions(+)

diff --git a/packages/react-native/Libraries/Pressability/Pressability.js b/packages/react-native/Libraries/Pressability/Pressability.js
index 0be465bec546..a84fd8cd1b1a 100644
--- a/packages/react-native/Libraries/Pressability/Pressability.js
+++ b/packages/react-native/Libraries/Pressability/Pressability.js
@@ -388,6 +388,10 @@ export default class Pressability {
     pageX: number,
     pageY: number,
   }>;
+  _touchGrantPosition: ?Readonly<{
+    pageX: number,
+    pageY: number,
+  }>;
   _touchActivateTime: ?number;
   _touchState: TouchState = 'NOT_RESPONDER';
 
@@ -710,6 +714,7 @@ export default class Pressability {
   ): void {
     if (isTerminalSignal(signal)) {
       this._touchActivatePosition = null;
+      this._touchGrantPosition = null;
       this._cancelLongPressDelayTimeout();
     }
 
@@ -720,6 +725,12 @@ export default class Pressability {
     const isActivationTransition =
       !isActivationSignal(prevState) && isActivationSignal(nextState);
 
+    if (isInitialTransition) {
+      const touch = getTouchFromPressEvent(event);
+      this._touchGrantPosition =
+        touch == null ? null : {pageX: touch.pageX, pageY: touch.pageY};
+    }
+
     if (isInitialTransition || isActivationTransition) {
       this._measureResponderRegion();
     }
@@ -826,6 +837,23 @@ export default class Pressability {
       right: pageX + width,
       top: pageY,
     };
+
+    // The responder was granted by a native hit test, so the touch that
+    // granted it must lie inside the view's true on-screen region. If the
+    // measured region excludes that touch, the measurement is stale — e.g. the
+    // view was repositioned by native code (sheet footers, modals) after
+    // layout, and `measure` still reports the pre-move frame. Using such a
+    // region would cancel the press on the first touch move, so discard it.
+    const grantPosition = this._touchGrantPosition;
+    if (
+      grantPosition != null &&
+      !this._isTouchWithinResponderRegion(
+        grantPosition as $FlowFixMe,
+        this._responderRegion,
+      )
+    ) {
+      this._responderRegion = null;
+    }
   };
 
   _isTouchWithinResponderRegion(
diff --git a/packages/react-native/Libraries/Pressability/__tests__/Pressability-test.js b/packages/react-native/Libraries/Pressability/__tests__/Pressability-test.js
index 05a46d31e9bd..ccc23ff1b56e 100644
--- a/packages/react-native/Libraries/Pressability/__tests__/Pressability-test.js
+++ b/packages/react-native/Libraries/Pressability/__tests__/Pressability-test.js
@@ -641,6 +641,70 @@ describe('Pressability', () => {
       jest.advanceTimersByTime(CONFIGURED_DEFAULT_MIN_PRESS_DURATION);
       expect(config.onPressOut).toBeCalled();
     });
+
+    it('is called when the measured region excludes the grant touch', () => {
+      // A view repositioned by native code after layout (e.g. a native sheet
+      // footer) measures at its stale layout position, far from where the
+      // press actually landed. Such a measurement must not be used to cancel
+      // the press on the first touch move.
+      mockUIManagerMeasure();
+      const {config, handlers} = createMockPressability();
+
+      handlers.onStartShouldSetResponder();
+      handlers.onResponderGrant(
+        createMockPressEvent({
+          registrationName: 'onResponderGrant',
+          pageX: 276,
+          pageY: 467,
+        }),
+      );
+      handlers.onResponderMove(
+        createMockPressEvent({
+          registrationName: 'onResponderMove',
+          pageX: 276,
+          pageY: 467,
+        }),
+      );
+      handlers.onResponderRelease(
+        createMockPressEvent({
+          registrationName: 'onResponderRelease',
+          pageX: 276,
+          pageY: 467,
+        }),
+      );
+
+      expect(config.onPress).toBeCalled();
+    });
+
+    it('is not called when the touch leaves a region containing the grant touch', () => {
+      mockUIManagerMeasure();
+      const {config, handlers} = createMockPressability();
+
+      handlers.onStartShouldSetResponder();
+      handlers.onResponderGrant(
+        createMockPressEvent({
+          registrationName: 'onResponderGrant',
+          pageX: 10,
+          pageY: 10,
+        }),
+      );
+      handlers.onResponderMove(
+        createMockPressEvent({
+          registrationName: 'onResponderMove',
+          pageX: 500,
+          pageY: 500,
+        }),
+      );
+      handlers.onResponderRelease(
+        createMockPressEvent({
+          registrationName: 'onResponderRelease',
+          pageX: 500,
+          pageY: 500,
+        }),
+      );
+
+      expect(config.onPress).not.toBeCalled();
+    });
   });
 
   describe('onPressIn', () => {