#400 accessibility: apply bold font system setting

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 
 ## <a id="unreleased"></a>[Unreleased]
 
+### Added
+
+- Accessibility: apply bold font system setting
+
 ## <a id="v1.7.4"></a>[v1.7.4] - 2022-11-11
 
 ### Added

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/AccessibilityHandler.kt

@@ -3,6 +3,7 @@ package deckers.thibault.aves.channel.calls
 import android.annotation.SuppressLint
 import android.content.Context
 import android.content.ContextWrapper
+import android.content.res.Configuration
 import android.os.Build
 import android.provider.Settings
 import android.util.Log
@@ -19,6 +20,7 @@ class AccessibilityHandler(private val contextWrapper: ContextWrapper) : MethodC
             "areAnimationsRemoved" -> safe(call, result, ::areAnimationsRemoved)
             "hasRecommendedTimeouts" -> safe(call, result, ::hasRecommendedTimeouts)
             "getRecommendedTimeoutMillis" -> safe(call, result, ::getRecommendedTimeoutMillis)
+            "shouldUseBoldFont" -> safe(call, result, ::shouldUseBoldFont)
             else -> result.notImplemented()
         }
     }
@@ -76,8 +78,28 @@ class AccessibilityHandler(private val contextWrapper: ContextWrapper) : MethodC
         result.success(millis)
     }
 
+    // Flutter v3.4 already checks the system `Configuration.fontWeightAdjustment` to update `MediaQuery`
+    // but we need to also check the non-standard Samsung field `bf` representing the bold font toggle
+    private fun shouldUseBoldFont(@Suppress("unused_parameter") call: MethodCall, result: MethodChannel.Result) {
+        var shouldBold = false
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+            val config = contextWrapper.resources.configuration
+            val fontWeightAdjustment = config.fontWeightAdjustment
+            shouldBold = if (fontWeightAdjustment != Configuration.FONT_WEIGHT_ADJUSTMENT_UNDEFINED && fontWeightAdjustment != 0) {
+                fontWeightAdjustment >= BOLD_TEXT_WEIGHT_ADJUSTMENT
+            } else {
+                // fallback to Samsung non-standard field
+                Regex(" bf=([01]) ").find(config.toString())?.groups?.get(1)?.value == "1"
+            }
+        }
+        result.success(shouldBold)
+    }
+
     companion object {
         private val LOG_TAG = LogUtils.createTag<AccessibilityHandler>()
         const val CHANNEL = "deckers.thibault/aves/accessibility"
+
+        // match Flutter way: https://github.com/flutter/engine/blob/main/shell/platform/android/io/flutter/view/AccessibilityBridge.java#L125
+        const val BOLD_TEXT_WEIGHT_ADJUSTMENT = 300
     }
 }

lib/services/accessibility_service.dart

@@ -4,6 +4,16 @@ import 'package:flutter/services.dart';
 class AccessibilityService {
   static const _platform = MethodChannel('deckers.thibault/aves/accessibility');
 
+  static Future<bool> shouldUseBoldFont() async {
+    try {
+      final result = await _platform.invokeMethod('shouldUseBoldFont');
+      if (result != null) return result as bool;
+    } on PlatformException catch (e, stack) {
+      await reportService.recordError(e, stack);
+    }
+    return false;
+  }
+
   static Future<bool> areAnimationsRemoved() async {
     try {
       final result = await _platform.invokeMethod('areAnimationsRemoved');

lib/widgets/aves_app.dart

@@ -108,6 +108,7 @@ class AvesApp extends StatefulWidget {
 class _AvesAppState extends State<AvesApp> with WidgetsBindingObserver {
   final ValueNotifier<AppMode> appModeNotifier = ValueNotifier(AppMode.main);
   late final Future<void> _appSetup;
+  late final Future<bool> _shouldUseBoldFontLoader;
   late final Future<CorePalette?> _dynamicColorPaletteLoader;
   final CollectionSource _mediaStoreSource = MediaStoreSource();
   final Debouncer _mediaStoreChangeDebouncer = Debouncer(delay: Durations.mediaContentChangeDebounceDelay);
@@ -129,6 +130,7 @@ class _AvesAppState extends State<AvesApp> with WidgetsBindingObserver {
     _appSetup = _setup();
     // remember screen size to use it later, when `context` and `window` are no longer reliable
     _screenSize = _getScreenSize();
+    _shouldUseBoldFontLoader = AccessibilityService.shouldUseBoldFont();
     _dynamicColorPaletteLoader = DynamicColorPlugin.getCorePalette();
     _mediaStoreChangeChannel.receiveBroadcastStream().listen((event) => _onMediaStoreChange(event as String?));
     _newIntentChannel.receiveBroadcastStream().listen((event) => _onNewIntent(event as Map?));
@@ -205,32 +207,43 @@ class _AvesAppState extends State<AvesApp> with WidgetsBindingObserver {
                                 lightAccent = Color(tonalPalette?.get(60) ?? defaultAccent.value);
                                 darkAccent = Color(tonalPalette?.get(70) ?? defaultAccent.value);
                               }
-                              return MaterialApp(
+                              return FutureBuilder<bool>(
-                                navigatorKey: AvesApp.navigatorKey,
+                                future: _shouldUseBoldFontLoader,
-                                home: home,
+                                builder: (context, snapshot) {
-                                navigatorObservers: _navigatorObservers,
+                                  // Flutter v3.4 already checks the system `Configuration.fontWeightAdjustment` to update `MediaQuery`
-                                builder: (context, child) {
+                                  // but we need to also check the non-standard Samsung field `bf` representing the bold font toggle
-                                  if (initialized) {
+                                  final shouldUseBoldFont = snapshot.data ?? false;
-                                    WidgetsBinding.instance.addPostFrameCallback((_) => AvesApp.setSystemUIStyle(context));
+                                  return MaterialApp(
-                                  }
+                                    navigatorKey: AvesApp.navigatorKey,
-                                  return AvesColorsProvider(
+                                    home: home,
-                                    child: Theme(
+                                    navigatorObservers: _navigatorObservers,
-                                      data: Theme.of(context).copyWith(
+                                    builder: (context, child) {
-                                        pageTransitionsTheme: pageTransitionsTheme,
+                                      if (initialized) {
-                                      ),
+                                        WidgetsBinding.instance.addPostFrameCallback((_) => AvesApp.setSystemUIStyle(context));
-                                      child: child!,
+                                      }
-                                    ),
+                                      return MediaQuery(
+                                        data: MediaQuery.of(context).copyWith(boldText: shouldUseBoldFont),
+                                        child: AvesColorsProvider(
+                                          child: Theme(
+                                            data: Theme.of(context).copyWith(
+                                              pageTransitionsTheme: pageTransitionsTheme,
+                                            ),
+                                            child: child!,
+                                          ),
+                                        ),
+                                      );
+                                    },
+                                    onGenerateTitle: (context) => context.l10n.appName,
+                                    theme: Themes.lightTheme(lightAccent, initialized),
+                                    darkTheme: themeBrightness == AvesThemeBrightness.black ? Themes.blackTheme(darkAccent, initialized) : Themes.darkTheme(darkAccent, initialized),
+                                    themeMode: themeBrightness.appThemeMode,
+                                    locale: settingsLocale,
+                                    localizationsDelegates: AppLocalizations.localizationsDelegates,
+                                    supportedLocales: AvesApp.supportedLocales,
+                                    // TODO TLAD remove custom scroll behavior when this is fixed: https://github.com/flutter/flutter/issues/82906
+                                    scrollBehavior: StretchMaterialScrollBehavior(),
                                   );
                                 },
-                                onGenerateTitle: (context) => context.l10n.appName,
-                                theme: Themes.lightTheme(lightAccent, initialized),
-                                darkTheme: themeBrightness == AvesThemeBrightness.black ? Themes.blackTheme(darkAccent, initialized) : Themes.darkTheme(darkAccent, initialized),
-                                themeMode: themeBrightness.appThemeMode,
-                                locale: settingsLocale,
-                                localizationsDelegates: AppLocalizations.localizationsDelegates,
-                                supportedLocales: AvesApp.supportedLocales,
-                                // TODO TLAD remove custom scroll behavior when this is fixed: https://github.com/flutter/flutter/issues/82906
-                                scrollBehavior: StretchMaterialScrollBehavior(),
                               );
                             },
                           );