Add ReducedMotionConfig component

apps/common-app/src/examples/ReducedMotionExample.tsx

@@ -11,6 +11,7 @@ import Animated, {
   withSpring,
   withSequence,
   ReduceMotion,
+  ReducedMotionConfig,
 } from 'react-native-reanimated';
 import {
   Gesture,
@@ -126,18 +127,31 @@ const EXAMPLES = [
 
 export default function ReducedMotionExample() {
   const [currentExample, setCurrentExample] = useState(0);
-
+  const [reduceMotion, setReduceMotion] = useState(ReduceMotion.Never);
   const { component, exampleList } = EXAMPLES[currentExample];
 
+  function handleReduceMotionModeChange() {
+    setReduceMotion(
+      reduceMotion === ReduceMotion.System
+        ? ReduceMotion.Never
+        : ReduceMotion.System
+    );
+  }
+
   return (
     <View style={styles.container}>
+      <Button
+        onPress={handleReduceMotionModeChange}
+        title={`Overwrite reduce motion: ${reduceMotion}`}
+      />
       {EXAMPLES.map((example, i) => (
         <Button
           key={i}
           onPress={() => setCurrentExample(i)}
           title={example.title}
         />
       ))}
+      <ReducedMotionConfig mode={reduceMotion} />
       {component}
       <View key={currentExample}>
         {exampleList.map((example, i) => {

packages/react-native-reanimated/src/PlatformChecker.ts

@@ -45,12 +45,3 @@ export function isWindowAvailable() {
   // @ts-ignore Fallback if `window` is undefined.
   return typeof window !== 'undefined';
 }
-
-export function isReducedMotion() {
-  return isWeb()
-    ? isWindowAvailable()
-      ? // @ts-ignore Fallback if `window` is undefined.
-        !window.matchMedia('(prefers-reduced-motion: no-preference)').matches
-      : false
-    : !!(global as localGlobal)._REANIMATED_IS_REDUCED_MOTION;
-}

packages/react-native-reanimated/src/ReducedMotion.ts

@@ -0,0 +1,24 @@
+import { isWeb, isWindowAvailable } from './PlatformChecker';
+import { makeMutable } from './mutables';
+
+type localGlobal = typeof global & Record<string, unknown>;
+
+export function isReducedMotionEnabledInSystem() {
+  return isWeb()
+    ? isWindowAvailable()
+      ? // @ts-ignore Fallback if `window` is undefined.
+        !window.matchMedia('(prefers-reduced-motion: no-preference)').matches
+      : false
+    : !!(global as localGlobal)._REANIMATED_IS_REDUCED_MOTION;
+}
+
+const IS_REDUCED_MOTION_ENABLED_IN_SYSTEM = isReducedMotionEnabledInSystem();
+
+export const ReducedMotionManager = {
+  jsValue: IS_REDUCED_MOTION_ENABLED_IN_SYSTEM,
+  uiValue: makeMutable(IS_REDUCED_MOTION_ENABLED_IN_SYSTEM),
+  setEnabled(value: boolean) {
+    ReducedMotionManager.jsValue = value;
+    ReducedMotionManager.uiValue.value = value;
+  },
+};

packages/react-native-reanimated/src/animation/util.ts

@@ -32,14 +32,14 @@ import {
   subtractMatrices,
   getRotationMatrix,
 } from './transformationMatrix/matrixUtils';
-import { isReducedMotion, shouldBeUseWeb } from '../PlatformChecker';
+import { shouldBeUseWeb } from '../PlatformChecker';
 import type { EasingFunction, EasingFunctionFactory } from '../Easing';
+import { ReducedMotionManager } from '../ReducedMotion';
 
 let IN_STYLE_UPDATER = false;
-const IS_REDUCED_MOTION = isReducedMotion();
 const SHOULD_BE_USE_WEB = shouldBeUseWeb();
 
-if (__DEV__ && IS_REDUCED_MOTION) {
+if (__DEV__ && ReducedMotionManager.jsValue) {
   console.warn(
     `[Reanimated] Reduced motion setting is enabled on this device. This warning is visible only in the development mode. Some animations will be disabled by default. You can override the behavior for individual animations, see https://docs.swmansion.com/react-native-reanimated/docs/guides/troubleshooting#reduced-motion-setting-is-enabled-on-this-device.`
   );
@@ -108,10 +108,11 @@ export function recognizePrefixSuffix(
  * Returns whether the motion should be reduced for a specified config.
  * By default returns the system setting.
  */
+const isReduceMotionOnUI = ReducedMotionManager.uiValue;
 export function getReduceMotionFromConfig(config?: ReduceMotion) {
   'worklet';
   return !config || config === ReduceMotion.System
-    ? IS_REDUCED_MOTION
+    ? isReduceMotionOnUI.value
     : config === ReduceMotion.Always;
 }
 

packages/react-native-reanimated/src/component/ReducedMotionConfig.tsx

@@ -0,0 +1,45 @@
+'use strict';
+import { useEffect } from 'react';
+import { ReduceMotion } from '../commonTypes';
+import {
+  ReducedMotionManager,
+  isReducedMotionEnabledInSystem,
+} from '../ReducedMotion';
+
+/**
+ * A component that lets you overwrite default reduce motion behavior globally in your application.
+ *
+ * @param mode - Determines default reduce motion behavior globally in your application. Configured with {@link ReduceMotion} enum.
+ * @see https://docs.swmansion.com/react-native-reanimated/docs/components/ReduceMotionConfig
+ */
+export function ReducedMotionConfig({ mode }: { mode: ReduceMotion }) {
+  useEffect(() => {
+    if (!__DEV__) {
+      return;
+    }
+    console.warn(
+      `[Reanimated] Reduced motion setting is overwritten with mode '${mode}'.`
+    );
+  }, []);
+
+  useEffect(() => {
+    const wasEnabled = ReducedMotionManager.jsValue;
+    switch (mode) {
+      case ReduceMotion.System:
+        const enabled = isReducedMotionEnabledInSystem();
+        ReducedMotionManager.setEnabled(enabled);
+        break;
+      case ReduceMotion.Always:
+        ReducedMotionManager.setEnabled(true);
+        break;
+      case ReduceMotion.Never:
+        ReducedMotionManager.setEnabled(false);
+        break;
+    }
+    return () => {
+      ReducedMotionManager.setEnabled(wasEnabled);
+    };
+  }, [mode]);
+
+  return null;
+}

packages/react-native-reanimated/src/hook/useReducedMotion.ts

@@ -1,7 +1,7 @@
 'use strict';
-import { isReducedMotion } from '../PlatformChecker';
+import { isReducedMotionEnabledInSystem } from '../ReducedMotion';
 
-const IS_REDUCED_MOTION = isReducedMotion();
+const IS_REDUCED_MOTION_ENABLED_IN_SYSTEM = isReducedMotionEnabledInSystem();
 
 /**
  * Lets you query the reduced motion system setting.
@@ -12,5 +12,5 @@ const IS_REDUCED_MOTION = isReducedMotion();
  * @see https://docs.swmansion.com/react-native-reanimated/docs/device/useReducedMotion
  */
 export function useReducedMotion() {
-  return IS_REDUCED_MOTION;
+  return IS_REDUCED_MOTION_ENABLED_IN_SYSTEM;
 }

packages/react-native-reanimated/src/index.ts

@@ -262,6 +262,7 @@ export {
 } from './jestUtils';
 export { LayoutAnimationConfig } from './component/LayoutAnimationConfig';
 export { PerformanceMonitor } from './component/PerformanceMonitor';
+export { ReducedMotionConfig } from './component/ReducedMotionConfig';
 export type {
   Adaptable,
   AdaptTransforms,

packages/react-native-reanimated/src/layoutReanimation/web/componentUtils.ts

@@ -16,11 +16,11 @@ import { scheduleAnimationCleanup } from './domUtils';
 import { _updatePropsJS } from '../../js-reanimated';
 import type { ReanimatedHTMLElement } from '../../js-reanimated';
 import { ReduceMotion } from '../../commonTypes';
-import { isReducedMotion } from '../../PlatformChecker';
 import { LayoutAnimationType } from '../animationBuilder/commonTypes';
 import type { ReanimatedSnapshot, ScrollOffsets } from './componentStyle';
 import { setElementPosition, snapshots } from './componentStyle';
 import { Keyframe } from '../animationBuilder';
+import { ReducedMotionManager } from '../../ReducedMotion';
 
 function getEasingFromConfig(config: CustomConfig): string {
   const easingName =
@@ -51,7 +51,7 @@ function getDelayFromConfig(config: CustomConfig): number {
 
 export function getReducedMotionFromConfig(config: CustomConfig) {
   if (!config.reduceMotionV) {
-    return isReducedMotion();
+    return ReducedMotionManager.jsValue;
   }
 
   switch (config.reduceMotionV) {
@@ -60,7 +60,7 @@ export function getReducedMotionFromConfig(config: CustomConfig) {
     case ReduceMotion.Always:
       return true;
     default:
-      return isReducedMotion();
+      return ReducedMotionManager.jsValue;
   }
 }