Add useAnimatedValue to public API

Summary:
Changelog:
[General][Added] - Introduce `useAnimatedValue` hook to make it easier working with `Animated.Value`s in function components.

Reviewed By: javache

Differential Revision: D40434219

fbshipit-source-id: 3caf6ad98d11a534b8cc6816820bc1d125150380

Author: fabriziocucci

Libraries/Animated/useAnimatedValue.d.ts

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import type {Animated} from './Animated';
+
+export function useAnimatedValue(
+  initialValue: number,
+  config?: Animated.AnimatedConfig,
+): Animated.Value;

Libraries/Animated/useAnimatedValue.js

@@ -0,0 +1,25 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import type {AnimatedValueConfig} from './nodes/AnimatedValue';
+
+import Animated from './Animated';
+import {useRef} from 'react';
+
+export default function useAnimatedValue(
+  initialValue: number,
+  config?: ?AnimatedValueConfig,
+): Animated.Value {
+  const ref = useRef(null);
+  if (ref.current == null) {
+    ref.current = new Animated.Value(initialValue, config);
+  }
+  return ref.current;
+}

index.js

@@ -80,6 +80,7 @@ import typeof * as Systrace from './Libraries/Performance/Systrace';
 import typeof ToastAndroid from './Libraries/Components/ToastAndroid/ToastAndroid';
 import typeof * as TurboModuleRegistry from './Libraries/TurboModule/TurboModuleRegistry';
 import typeof UIManager from './Libraries/ReactNative/UIManager';
+import typeof useAnimatedValue from './Libraries/Animated/useAnimatedValue';
 import typeof useColorScheme from './Libraries/Utilities/useColorScheme';
 import typeof useWindowDimensions from './Libraries/Utilities/useWindowDimensions';
 import typeof UTFSequence from './Libraries/UTFSequence';
@@ -373,6 +374,9 @@ module.exports = {
     return require('./Libraries/ReactNative/RendererProxy')
       .unstable_batchedUpdates;
   },
+  get useAnimatedValue(): useAnimatedValue {
+    return require('./Libraries/Animated/useAnimatedValue').default;
+  },
   get useColorScheme(): useColorScheme {
     return require('./Libraries/Utilities/useColorScheme').default;
   },

types/index.d.ts

@@ -76,6 +76,7 @@ export * from '../Libraries/ActionSheetIOS/ActionSheetIOS';
 export * from '../Libraries/Alert/Alert';
 export * from '../Libraries/Animated/Animated';
 export * from '../Libraries/Animated/Easing';
+export * from '../Libraries/Animated/useAnimatedValue';
 export * from '../Libraries/AppState/AppState';
 export * from '../Libraries/BatchedBridge/NativeModules';
 export * from '../Libraries/Components/AccessibilityInfo/AccessibilityInfo';