Use FRNFontMetrics module in Text

apps/fluent-tester/ios/Podfile

@@ -24,6 +24,9 @@ use_test_app! do |target|
   target.app do
     platform :ios, '14.0'
 
+    # There is a bug where autolinking isn't working, do specify these manually.
+    pod 'FRNFontMetrics', :path => '../../../packages/experimental/NativeFontMetrics/FRNFontMetrics.podspec'
+
     script_phase name: 'Start Packager',
                  script: start_packager_script,
                  execution_position: :before_compile

apps/fluent-tester/ios/Podfile.lock

@@ -10,12 +10,14 @@ PODS:
     - React-jsi (= 0.68.5)
     - ReactCommon/turbomodule/core (= 0.68.5)
   - fmt (6.2.1)
-  - FRNAvatar (0.16.20):
+  - FRNAvatar (0.16.24):
     - MicrosoftFluentUI (= 0.8.3)
     - React
   - FRNDatePicker (0.7.3):
     - MicrosoftFluentUI (= 0.8.3)
     - React
+  - FRNFontMetrics (0.2.0):
+    - React
   - glog (0.3.5)
   - MicrosoftFluentUI (0.8.3):
     - MicrosoftFluentUI/ActivityIndicator_ios (= 0.8.3)
@@ -384,7 +386,7 @@ PODS:
     - glog
   - react-native-menu (0.1.2):
     - React
-  - react-native-slider (4.3.2):
+  - react-native-slider (4.3.3):
     - React-Core
   - React-perflogger (0.68.5)
   - React-RCTActionSheet (0.68.5):
@@ -468,6 +470,7 @@ DEPENDENCIES:
   - FBReactNativeSpec (from `../../../node_modules/react-native/React/FBReactNativeSpec`)
   - FRNAvatar (from `../../../packages/experimental/Avatar`)
   - FRNDatePicker (from `../../../packages/experimental/NativeDatePicker`)
+  - FRNFontMetrics (from `../../../packages/experimental/NativeFontMetrics/FRNFontMetrics.podspec`)
   - glog (from `../../../node_modules/react-native/third-party-podspecs/glog.podspec`)
   - RCT-Folly (from `../../../node_modules/react-native/third-party-podspecs/RCT-Folly.podspec`)
   - RCTRequired (from `../../../node_modules/react-native/Libraries/RCTRequired`)
@@ -522,6 +525,8 @@ EXTERNAL SOURCES:
     :path: "../../../packages/experimental/Avatar"
   FRNDatePicker:
     :path: "../../../packages/experimental/NativeDatePicker"
+  FRNFontMetrics:
+    :path: "../../../packages/experimental/NativeFontMetrics/FRNFontMetrics.podspec"
   glog:
     :podspec: "../../../node_modules/react-native/third-party-podspecs/glog.podspec"
   RCT-Folly:
@@ -595,8 +600,9 @@ SPEC CHECKSUMS:
   FBLazyVector: 2b47ff52037bd9ae07cc9b051c9975797814b736
   FBReactNativeSpec: dd89c4a5591e20015aa55c6efbf9c7740a83efbf
   fmt: ff9d55029c625d3757ed641535fd4a75fedc7ce9
-  FRNAvatar: de1aec8a9011ade478f2148677b4f2c076d77110
+  FRNAvatar: 3911021ed95a08f19e0ee696712aa48b6dff010a
   FRNDatePicker: 241cd55b8d2b63d4427d782951f31504f09fbe1a
+  FRNFontMetrics: 472e7952e454ece364a91babd8bb2a32219676e7
   glog: 476ee3e89abb49e07f822b48323c51c57124b572
   MicrosoftFluentUI: e30487dd18aba04beeed4caf1ce1988073f8b03a
   RCT-Folly: 4d8508a426467c48885f1151029bc15fa5d7b3b8
@@ -613,7 +619,7 @@ SPEC CHECKSUMS:
   React-jsinspector: eb202e43b3879aba9a14f3f65788aec85d4e1ea9
   React-logger: 98f663b292a60967ebbc6d803ae96c1381183b6d
   react-native-menu: 9fe07f72e075b250295eeae25425490cc9608951
-  react-native-slider: e540525ea731783850802b7af457d8551edb0711
+  react-native-slider: 7d19220da2f2ae7cbb9aa80127cb73c597fa221f
   React-perflogger: 0458a87ea9a7342079e7a31b0d32b3734fb8415f
   React-RCTActionSheet: 22538001ea2926dea001111dd2846c13a0730bc9
   React-RCTAnimation: 732ce66878d4aa151d56a0d142b1105aa12fd313
@@ -632,6 +638,6 @@ SPEC CHECKSUMS:
   RNSVG: 302bfc9905bd8122f08966dc2ce2d07b7b52b9f8
   Yoga: c4d61225a466f250c35c1ee78d2d0b3d41fe661c
 
-PODFILE CHECKSUM: eeba196fb25cf059c631787109cecd08a4ac85a6
+PODFILE CHECKSUM: 819f14a4e3e6e335a0b1993fe37edad50db02d86
 
 COCOAPODS: 1.11.3

change/@fluentui-react-native-experimental-native-font-metrics-a7673fa7-cc45-446e-83e0-02ce3ab92578.json

@@ -0,0 +1,7 @@
+{
+  "type": "minor",
+  "comment": "Send new font metrics information through a JS event",
+  "packageName": "@fluentui-react-native/experimental-native-font-metrics",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

change/@fluentui-react-native-tester-955d714f-c8eb-47c4-bec6-5a032f9171d2.json

@@ -0,0 +1,7 @@
+{
+  "type": "minor",
+  "comment": "Add Dynamic Type support",
+  "packageName": "@fluentui-react-native/tester",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

change/@fluentui-react-native-text-234cd2bf-f18b-4347-8a20-cfe76b66a60d.json

@@ -0,0 +1,7 @@
+{
+  "type": "minor",
+  "comment": "Add Dynamic Type support",
+  "packageName": "@fluentui-react-native/text",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

package.nuspec

@@ -12,10 +12,12 @@
     <!-- iOS device ship -->
     <file src="DerivedData\Build\Products\Release-iphoneos\FRNAvatar\libFRNAvatar.a" target="Ship-iphoneos"/>
     <file src="DerivedData\Build\Products\Release-iphoneos\FRNDatePicker\libFRNDatePicker.a" target="Ship-iphoneos"/>
+    <file src="DerivedData\Build\Products\Release-iphoneos\FRNFontMetrics\libFRNFontMetrics.a" target="Ship-iphoneos"/>
 
     <!-- iOS simulator ship -->
     <file src="DerivedData\Build\Products\Release-iphonesimulator\FRNAvatar\libFRNAvatar.a" target="Ship-iphonesimulator"/>
     <file src="DerivedData\Build\Products\Release-iphonesimulator\FRNDatePicker\libFRNDatePicker.a" target="Ship-iphonesimulator"/>
+    <file src="DerivedData\Build\Products\Release-iphonesimulator\FRNFontMetrics\libFRNFontMetrics.a" target="Ship-iphoneos"/>
 
     <!-- macOS ship -->
     <file src="DerivedData\Build\Products\Release\FRNAvatar\libFRNAvatar.a" target="Ship-macosx"/>

packages/components/text/package.json

@@ -28,6 +28,7 @@
   "dependencies": {
     "@uifabricshared/foundation-compose": "^1.12.21",
     "@fluentui-react-native/adapters": ">=0.10.0 <1.0.0",
+    "@fluentui-react-native/experimental-native-font-metrics": "^0.2.0",
     "@fluentui-react-native/framework": "0.8.20",
     "@fluentui-react-native/interactive-hooks": ">=0.21.1 <1.0.0",
     "@fluentui-react-native/theme-tokens": ">=0.21.3 <1.0.0",

packages/components/text/src/Text.tsx

@@ -15,6 +15,7 @@ import { I18nManager, Platform, Text as RNText } from 'react-native';
 import { textName, TextProps, TextTokens } from './Text.types';
 import { useTextTokens } from './TextTokens';
 import React from 'react';
+import { useFontMetricsScaleFactors } from '@fluentui-react-native/experimental-native-font-metrics';
 
 const emptyProps = {};
 export const Text = compressible<TextProps, TextTokens>((props: TextProps, useTokens: UseTokens<TextTokens>) => {
@@ -49,6 +50,9 @@ export const Text = compressible<TextProps, TextTokens>((props: TextProps, useTo
   // get the tokens from the theme
   let [tokens, cache] = useTokens(theme);
 
+  // TODO(#2268): Remove once RN Core properly supports Dynamic Type scaling
+  const fontMetricsScaleFactors = useFontMetricsScaleFactors();
+
   const textAlign = I18nManager.isRTL
     ? align === 'start'
       ? 'right'
@@ -79,6 +83,9 @@ export const Text = compressible<TextProps, TextTokens>((props: TextProps, useTo
     [onPress, onAccessibilityTap],
   );
 
+  // TODO(#2268): Remove once RN Core properly supports Dynamic Type scaling
+  const dynamicTypeVariant = Platform.OS === 'ios' ? tokens.dynamicTypeRamp : undefined;
+
   // override tokens from props
   [tokens, cache] = patchTokens(tokens, cache, {
     color,
@@ -106,6 +113,19 @@ export const Text = compressible<TextProps, TextTokens>((props: TextProps, useTo
     ['color', 'fontStyle', 'textAlign', 'textDecorationLine', ...fontStyles.keys],
   );
 
+  // [TODO(#2268): Remove once RN Core properly supports Dynamic Type scaling
+  let scaleStyleAdjustments: TextTokens = emptyProps;
+  // tokenStyle.fontSize and tokenStyle.lineHeight can also be strings (e.g., "14px").
+  // Therefore, we only support scaling for number-based size values in order to avoid any messy calculations.
+  if (dynamicTypeVariant !== undefined && typeof tokenStyle.fontSize === 'number' && typeof tokenStyle.lineHeight === 'number') {
+    const scaleFactor = fontMetricsScaleFactors[dynamicTypeVariant] ?? 1;
+    scaleStyleAdjustments = {
+      fontSize: tokenStyle.fontSize * scaleFactor,
+      lineHeight: tokenStyle.lineHeight * scaleFactor,
+    };
+  }
+  // ]TODO(#2268)
+
   const isWinPlatform = Platform.OS === (('win32' as any) || 'windows');
   const filteredProps = {
     onKeyUp: isWinPlatform ? onKeyUp : undefined,
@@ -126,7 +146,8 @@ export const Text = compressible<TextProps, TextTokens>((props: TextProps, useTo
       ...extra,
       onPress,
       numberOfLines: truncate || !wrap ? 1 : 0,
-      style: mergeStyles(tokenStyle, props.style, extra?.style),
+      style: mergeStyles(tokenStyle, props.style, extra?.style, scaleStyleAdjustments),
+      ...(dynamicTypeVariant !== undefined && { allowFontScaling: false }), // TODO(#2268): Remove once RN Core properly supports Dynamic Type scaling
     };
     return (
       <RNText ellipsizeMode={!wrap && !truncate ? 'clip' : 'tail'} {...mergedProps}>

packages/components/text/src/Text.types.ts

@@ -8,7 +8,11 @@ export const textName = 'Text';
  * Text tokens, these are the internally configurable values for Text elements. In particular these
  * drive decisions on how to build the styles
  */
-export type TextTokens = Omit<FontTokens, 'fontFamily'> & IForegroundColorTokens & Omit<TextStyle, 'fontSize' | 'fontWeight' | 'color'>;
+export type TextTokens = Omit<FontTokens, 'fontFamily'> &
+  IForegroundColorTokens &
+  Omit<TextStyle, 'fontSize' | 'fontWeight' | 'color'> & {
+    dynamicTypeRamp?: string; // TODO(#2268): Remove once RN Core properly supports Dynamic Type scaling
+  };
 
 export type TextAlign = 'start' | 'center' | 'end' | 'justify';
 export type TextFont = 'base' | 'monospace' | 'numeric';

packages/components/text/src/Variants.ios.ts

@@ -1,43 +1,57 @@
 import { Text } from './Text';
 
+// TODO(#2268): Remove "as any" designations once RN Core properly supports Dynamic Type scaling
+
 export const Caption1 = Text.customize({
   variant: 'caption1',
-});
+  dynamicTypeRamp: 'footnote',
+} as any);
 export const Caption1Strong = Text.customize({
   variant: 'caption1Strong',
-});
+  dynamicTypeRamp: 'footnote',
+} as any);
 export const Caption2 = Text.customize({
   variant: 'caption2',
-});
+  dynamicTypeRamp: 'caption1',
+} as any);
 export const Body1 = Text.customize({
   variant: 'body1',
-});
+  dynamicTypeRamp: 'body',
+} as any);
 export const Body1Strong = Text.customize({
   variant: 'body1Strong',
-});
+  dynamicTypeRamp: 'body',
+} as any);
 export const Body2 = Text.customize({
   variant: 'body2',
-});
+  dynamicTypeRamp: 'subheadline',
+} as any);
 export const Body2Strong = Text.customize({
   variant: 'body2Strong',
-});
+  dynamicTypeRamp: 'subheadline',
+} as any);
 export const Subtitle1 = null; // Not supported on iOS
 export const Subtitle1Strong = null; // Not supported on iOS
 export const Subtitle2 = null; // Not supported on iOS
 export const Subtitle2Strong = null; // Not supported on iOS
 export const Title1 = Text.customize({
   variant: 'title1',
-});
+  dynamicTypeRamp: 'title1',
+} as any);
 export const Title1Strong = null; // Not supported on iOS
 export const Title2 = Text.customize({
   variant: 'title2',
-});
+  dynamicTypeRamp: 'title2',
+} as any);
 export const Title3 = Text.customize({
   variant: 'title3',
-});
+  dynamicTypeRamp: 'title3',
+} as any);
 export const LargeTitle = Text.customize({
   variant: 'largeTitle',
-});
+  dynamicTypeRamp: 'largeTitle',
+} as any);
 export const Display = Text.customize({
   variant: 'display',
-});
+  dynamicTypeRamp: 'largeTitle',
+} as any);

packages/experimental/NativeFontMetrics/ios/FRNFontMetrics.m

@@ -85,7 +85,7 @@ + (BOOL)requiresMainQueueSetup
     return YES;
 }
 
-RCT_EXPORT_BLOCKING_SYNCHRONOUS_METHOD(allScaleFactors)
+RCT_EXPORT_BLOCKING_SYNCHRONOUS_METHOD(currentScaleFactors)
 {
     NSMutableDictionary *result = [NSMutableDictionary new];
     [FRNRecognizedTextStyles() enumerateKeysAndObjectsUsingBlock:^(NSString * styleString, __unused NSNumber * boxedTextStyle, __unused BOOL * stop) {
@@ -129,7 +129,7 @@ - (void)stopObserving
 
 - (void)onFontMetricsChanged:(NSNotification *)notification {
     if (_hasListeners) {
-        [self sendEventWithName:@"onFontMetricsChanged" body:@{@"newScaleFactors": [self allScaleFactors]}];
+        [self sendEventWithName:@"onFontMetricsChanged" body:@{@"newScaleFactors": [self currentScaleFactors]}];
     }
 }
 

packages/experimental/NativeFontMetrics/src/NativeFontMetrics.ios.ts

@@ -4,7 +4,8 @@ import { ScaleFactors, TextStyle } from './NativeFontMetrics.types';
 export const NativeFontMetrics = NativeModules.FRNFontMetrics;
 
 interface NativeFontMetricsInterface {
-  allScaleFactors(): ScaleFactors;
+  currentScaleFactors(): ScaleFactors;
   scaleFactorForStyle(style: TextStyle): number;
 }
+
 export default NativeFontMetrics as NativeFontMetricsInterface;

packages/experimental/NativeFontMetrics/src/NativeFontMetrics.ts

@@ -1,12 +1,11 @@
-import { ScaleFactors, TextStyle } from './NativeFontMetrics.types';
+import { TextStyle } from './NativeFontMetrics.types';
 
-interface NativeFontMetricsInterface {
-  allScaleFactors(): ScaleFactors;
-  scaleFactorForStyle(style: TextStyle): number;
-}
-
-const NativeFontMetrics: NativeFontMetricsInterface = {
-  allScaleFactors: () => {
+const NativeFontMetrics = {
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  addListener: (_: string) => {},
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  removeListeners: (_: number) => {},
+  currentScaleFactors: () => {
     console.warn('NativeFontMetrics is only available on iOS');
     return {};
   },

packages/experimental/NativeFontMetrics/src/NativeFontMetrics.types.ts

@@ -1,3 +1,9 @@
+export interface FontMetrics {
+  readonly scaleFactors: ScaleFactors;
+}
+
+export type ScaleFactors = { [K in TextStyle]?: number };
+
 export type TextStyle =
   | 'caption2'
   | 'caption1'
@@ -10,5 +16,3 @@ export type TextStyle =
   | 'title2'
   | 'title1'
   | 'largeTitle';
-
-export type ScaleFactors = { [K in TextStyle]?: number };

packages/experimental/NativeFontMetrics/src/fontMetrics.ios.ts

@@ -0,0 +1,25 @@
+import { NativeEventEmitter } from 'react-native';
+import NativeFontMetrics from './NativeFontMetrics';
+import { FontMetrics, ScaleFactors } from './NativeFontMetrics.types';
+
+class FontMetricsImpl implements FontMetrics {
+  _scaleFactors: ScaleFactors;
+
+  constructor() {
+    if (NativeFontMetrics) {
+      this._scaleFactors = NativeFontMetrics.currentScaleFactors();
+      const eventEmitter = new NativeEventEmitter(NativeFontMetrics as any);
+      eventEmitter.addListener('onFontMetricsChanged', ({ newScaleFactors }) => {
+        this._scaleFactors = newScaleFactors;
+      });
+    } else {
+      this._scaleFactors = {};
+    }
+  }
+
+  get scaleFactors(): ScaleFactors {
+    return this._scaleFactors;
+  }
+}
+
+export const fontMetrics = new FontMetricsImpl() as FontMetrics;

packages/experimental/NativeFontMetrics/src/fontMetrics.ts

@@ -0,0 +1,3 @@
+import { FontMetrics } from './NativeFontMetrics.types';
+
+export const fontMetrics = { scaleFactors: {} } as FontMetrics;

packages/experimental/NativeFontMetrics/src/index.ts

@@ -1,2 +1 @@
-export * from './NativeFontMetrics';
 export * from './useFontMetrics';

packages/experimental/NativeFontMetrics/src/useFontMetrics.ios.ts

@@ -0,0 +1,29 @@
+import { useMemo } from 'react';
+import { NativeEventEmitter } from 'react-native';
+import { useSubscription } from 'use-subscription';
+import { fontMetrics } from './fontMetrics';
+import NativeFontMetrics from './NativeFontMetrics';
+import { ScaleFactors } from './NativeFontMetrics.types';
+
+const eventEmitter = NativeFontMetrics ? new NativeEventEmitter(NativeFontMetrics as any) : undefined;
+
+export function useFontMetricsScaleFactors(): ScaleFactors {
+  if (!eventEmitter) {
+    return {};
+  }
+
+  const subscription = useMemo(
+    () => ({
+      getCurrentValue: () => fontMetrics.scaleFactors,
+      subscribe: (callback) => {
+        const appearanceSubscription = eventEmitter.addListener('onFontMetricsChanged', callback);
+        return () => {
+          appearanceSubscription.remove();
+        };
+      },
+    }),
+    [],
+  );
+
+  return useSubscription(subscription);
+}