caption change effect

lib/theme/durations.dart

@@ -96,6 +96,7 @@ class DurationsData {
   // common animations
   final Duration expansionTileAnimation;
   final Duration formTransition;
+  final Duration formTextStyleTransition;
   final Duration chartTransition;
   final Duration iconAnimation;
   final Duration staggeredAnimation;
@@ -112,6 +113,7 @@ class DurationsData {
   const DurationsData({
     this.expansionTileAnimation = const Duration(milliseconds: 200),
     this.formTransition = const Duration(milliseconds: 200),
+    this.formTextStyleTransition = const Duration(milliseconds: 800),
     this.chartTransition = const Duration(milliseconds: 400),
     this.iconAnimation = const Duration(milliseconds: 300),
     this.staggeredAnimation = const Duration(milliseconds: 375),
@@ -126,6 +128,7 @@ class DurationsData {
       // as of Flutter v2.5.1, `ExpansionPanelList` throws if animation duration is zero
       expansionTileAnimation: const Duration(microseconds: 1),
       formTransition: Duration.zero,
+      formTextStyleTransition: Duration.zero,
       chartTransition: Duration.zero,
       iconAnimation: Duration.zero,
       staggeredAnimation: Duration.zero,

lib/widgets/common/basic/animated_text.dart

@@ -0,0 +1,86 @@
+import 'package:collection/collection.dart';
+import 'package:flutter/material.dart';
+
+class AnimatedText extends StatefulWidget {
+  final String data;
+  final TextStyle style, changedStyle;
+  final Curve curve;
+  final Duration duration;
+
+  const AnimatedText(
+    this.data, {
+    super.key,
+    required this.style,
+    required this.changedStyle,
+    this.curve = Curves.linear,
+    required this.duration,
+  });
+
+  @override
+  State<AnimatedText> createState() => _AnimatedTextState();
+}
+
+class _AnimatedTextState extends State<AnimatedText> with SingleTickerProviderStateMixin {
+  late final AnimationController _controller;
+  late final Animation<TextStyle> _style;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller = AnimationController(
+      duration: widget.duration,
+      vsync: this,
+    )
+      ..value = 1
+      ..addListener(() => setState(() {}));
+    _style = _ShadowedTextStyleTween(begin: widget.changedStyle, end: widget.style).animate(CurvedAnimation(
+      parent: _controller,
+      curve: widget.curve,
+    ));
+  }
+
+  @override
+  void didUpdateWidget(AnimatedText oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (oldWidget.data != widget.data) {
+      _controller
+        ..value = 0
+        ..forward();
+    }
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Text(
+      widget.data,
+      style: _style.value,
+    );
+  }
+}
+
+class _ShadowedTextStyleTween extends Tween<TextStyle> {
+  _ShadowedTextStyleTween({super.begin, super.end});
+
+  @override
+  TextStyle lerp(double t) {
+    final textStyle = TextStyle.lerp(begin, end, t)!;
+    final beginShadows = begin!.shadows;
+    final endShadows = end!.shadows;
+    if (beginShadows != null && endShadows != null && beginShadows.length == endShadows.length) {
+      return textStyle.copyWith(
+        shadows: beginShadows.mapIndexed((i, a) {
+          final b = endShadows[i];
+          return Shadow.lerp(a, b, t)!;
+        }).toList(),
+      );
+    } else {
+      return textStyle;
+    }
+  }
+}

lib/widgets/common/basic/circle.dart

@@ -29,13 +29,13 @@ class _CircularIndicatorState extends State<CircularIndicator> {
       child: Stack(
         alignment: Alignment.center,
         children: [
-          Circle(
+          _Circle(
             radius: widget.radius,
             lineWidth: widget.lineWidth,
             percent: 1.0,
             color: widget.background,
           ),
-          Circle(
+          _Circle(
             radius: widget.radius,
             lineWidth: widget.lineWidth,
             percent: widget.percent,
@@ -48,11 +48,11 @@ class _CircularIndicatorState extends State<CircularIndicator> {
   }
 }
 
-class Circle extends StatelessWidget {
+class _Circle extends StatelessWidget {
   final double radius, lineWidth, percent;
   final Color color;
 
-  const Circle({
+  const _Circle({
     super.key,
     required this.radius,
     required this.lineWidth,

lib/widgets/common/basic/multi_cross_fader.dart

@@ -33,7 +33,7 @@ class _MultiCrossFaderState extends State<MultiCrossFader> {
   @override
   void didUpdateWidget(covariant MultiCrossFader oldWidget) {
     super.didUpdateWidget(oldWidget);
-    if (_first == oldWidget.child) {
+    if (oldWidget.child == _first) {
       _second = widget.child;
       _fadeState = CrossFadeState.showSecond;
     } else {

lib/widgets/common/identity/aves_caption.dart

@@ -0,0 +1,42 @@
+import 'package:aves/theme/durations.dart';
+import 'package:aves/widgets/common/basic/animated_text.dart';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+class AvesCaption extends StatelessWidget {
+  final String data;
+
+  const AvesCaption(
+    this.data, {
+    super.key,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final subtitleStyle = theme.textTheme.caption!;
+    final subtitleChangeShadowColor = theme.colorScheme.onPrimary;
+    return AnimatedText(
+      // provide key to refresh on theme brightness change
+      key: ValueKey(subtitleChangeShadowColor),
+      data,
+      style: subtitleStyle.copyWith(
+        shadows: [
+          Shadow(
+            color: subtitleChangeShadowColor.withOpacity(0),
+            blurRadius: 0,
+          )
+        ],
+      ),
+      changedStyle: subtitleStyle.copyWith(
+        shadows: [
+          Shadow(
+            color: subtitleChangeShadowColor,
+            blurRadius: 3,
+          )
+        ],
+      ),
+      duration: context.read<DurationsData>().formTextStyleTransition,
+    );
+  }
+}

lib/widgets/common/search/page.dart

@@ -38,7 +38,7 @@ class _SearchPageState extends State<SearchPage> {
   @override
   void didUpdateWidget(covariant SearchPage oldWidget) {
     super.didUpdateWidget(oldWidget);
-    if (widget.delegate != oldWidget.delegate) {
+    if (oldWidget.delegate != widget.delegate) {
       _unregisterWidget(oldWidget);
       _registerWidget(widget);
     }

lib/widgets/dialogs/tile_view_dialog.dart

@@ -3,6 +3,7 @@ import 'package:aves/theme/icons.dart';
 import 'package:aves/theme/themes.dart';
 import 'package:aves/widgets/common/basic/text_dropdown_button.dart';
 import 'package:aves/widgets/common/extensions/build_context.dart';
+import 'package:aves/widgets/common/identity/aves_caption.dart';
 import 'package:aves/widgets/common/identity/highlight_title.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
@@ -76,12 +77,7 @@ class _TileViewDialogState<S, G, L> extends State<TileViewDialog<S, G, L>> with
             _selectedSort = v;
             _reverseSort = false;
           },
-          bottom: _selectedSort != null
-              ? Text(
-                  widget.sortOrder(_selectedSort as S, _reverseSort),
-                  style: Theme.of(context).textTheme.caption,
-                )
-              : null,
+          bottom: _selectedSort != null ? AvesCaption(widget.sortOrder(_selectedSort as S, _reverseSort)) : null,
         ),
         AnimatedSwitcher(
           duration: context.read<DurationsData>().formTransition,

lib/widgets/settings/common/tiles.dart

@@ -1,5 +1,6 @@
 import 'package:aves/model/settings/settings.dart';
 import 'package:aves/theme/durations.dart';
+import 'package:aves/widgets/common/identity/aves_caption.dart';
 import 'package:aves/widgets/dialogs/aves_selection_dialog.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
@@ -103,7 +104,7 @@ class SettingsSelectionListTile<T extends Enum> extends StatelessWidget {
       selector: selector,
       builder: (context, current, child) => ListTile(
         title: Text(tileTitle),
-        subtitle: Text(getName(context, current)),
+        subtitle: AvesCaption(getName(context, current)),
         onTap: () => showSelectionDialog<T>(
           context: context,
           builder: (context) => AvesSelectionDialog<T>(

lib/widgets/settings/privacy/file_picker/crumb_line.dart

@@ -25,7 +25,7 @@ class _CrumbLineState extends State<CrumbLine> {
   @override
   void didUpdateWidget(covariant CrumbLine oldWidget) {
     super.didUpdateWidget(oldWidget);
-    if (widget.directory.relativeDir.length > oldWidget.directory.relativeDir.length) {
+    if (oldWidget.directory.relativeDir.length < widget.directory.relativeDir.length) {
       // scroll to show last crumb
       WidgetsBinding.instance.addPostFrameCallback((_) {
         final extent = _controller.position.maxScrollExtent;