explorer fixes

android/app/src/main/AndroidManifest.xml

@@ -323,8 +323,10 @@
         <meta-data
             android:name="flutterEmbedding"
             android:value="2" />
-        <!-- as of Flutter v3.22.0 (stable),
-        Impeller fails to render videos (via `ffmpegkit`), and has random glitches -->
+        <!--
+        Impeller is not supported by `media_kit` v1.1.10+1:
+        https://github.com/media-kit/media-kit/issues/707
+        -->
         <meta-data
             android:name="io.flutter.embedding.android.EnableImpeller"
             android:value="false" />

lib/widgets/explorer/app_bar.dart

@@ -26,7 +26,7 @@ import 'package:flutter/scheduler.dart';
 import 'package:provider/provider.dart';
 
 class ExplorerAppBar extends StatefulWidget {
-  final ValueNotifier<VolumeRelativeDirectory> directoryNotifier;
+  final ValueNotifier<VolumeRelativeDirectory?> directoryNotifier;
   final void Function(String path) goTo;
 
   const ExplorerAppBar({
@@ -67,7 +67,7 @@ class _ExplorerAppBarState extends State<ExplorerAppBar> with WidgetsBindingObse
           return SizedBox(
             width: constraints.maxWidth,
             height: CrumbLine.getPreferredHeight(MediaQuery.textScalerOf(context)),
-            child: ValueListenableBuilder<VolumeRelativeDirectory>(
+            child: ValueListenableBuilder<VolumeRelativeDirectory?>(
               valueListenable: widget.directoryNotifier,
               builder: (context, directory, child) {
                 return CrumbLine(
@@ -128,7 +128,9 @@ class _ExplorerAppBarState extends State<ExplorerAppBar> with WidgetsBindingObse
           // wait for the popup menu to hide before proceeding with the action
           await Future.delayed(animations.popUpAnimationDelay * timeDilation);
           final directory = widget.directoryNotifier.value;
-          ExplorerActionDelegate(directory: directory).onActionSelected(context, action);
+          if (directory != null) {
+            ExplorerActionDelegate(directory: directory).onActionSelected(context, action);
+          }
         },
         popUpAnimationStyle: animations.popUpAnimationStyle,
       ),
@@ -137,10 +139,10 @@ class _ExplorerAppBarState extends State<ExplorerAppBar> with WidgetsBindingObse
 
   Widget _buildVolumeSelector(BuildContext context) {
     if (_volumes.length == 2) {
-      return ValueListenableBuilder<VolumeRelativeDirectory>(
+      return ValueListenableBuilder<VolumeRelativeDirectory?>(
         valueListenable: widget.directoryNotifier,
         builder: (context, directory, child) {
-          final currentVolume = directory.volumePath;
+          final currentVolume = directory?.volumePath;
           final otherVolume = _volumes.firstWhere((volume) => volume.path != currentVolume);
           final icon = otherVolume.isRemovable ? AIcons.storageCard : AIcons.storageMain;
           return IconButton(
@@ -155,7 +157,7 @@ class _ExplorerAppBarState extends State<ExplorerAppBar> with WidgetsBindingObse
         icon: const Icon(AIcons.storageCard),
         onPressed: () async {
           _volumes.map((v) {
-            final selected = widget.directoryNotifier.value.volumePath == v.path;
+            final selected = widget.directoryNotifier.value?.volumePath == v.path;
             final icon = v.isRemovable ? AIcons.storageCard : AIcons.storageMain;
             return PopupMenuItem(
               value: v,
@@ -166,7 +168,7 @@ class _ExplorerAppBarState extends State<ExplorerAppBar> with WidgetsBindingObse
               ),
             );
           }).toList();
-          final volumePath = widget.directoryNotifier.value.volumePath;
+          final volumePath = widget.directoryNotifier.value?.volumePath;
           final initialVolume = _volumes.firstWhereOrNull((v) => v.path == volumePath);
           final volume = await showDialog<StorageVolume?>(
             context: context,

lib/widgets/explorer/explorer_page.dart

@@ -41,15 +41,13 @@ class ExplorerPage extends StatefulWidget {
 
 class _ExplorerPageState extends State<ExplorerPage> {
   final List<StreamSubscription> _subscriptions = [];
-  final ValueNotifier<VolumeRelativeDirectory> _directory = ValueNotifier(const VolumeRelativeDirectory(volumePath: '', relativeDir: ''));
+  final ValueNotifier<VolumeRelativeDirectory?> _directory = ValueNotifier(null);
+  final ValueNotifier<VolumeRelativeDirectory?> _contentsDirectory = ValueNotifier(null);
   final ValueNotifier<List<Directory>> _contents = ValueNotifier([]);
 
   Set<StorageVolume> get _volumes => androidFileUtils.storageVolumes;
 
-  String get _currentDirectoryPath {
-    final dir = _directory.value;
-    return pContext.join(dir.volumePath, dir.relativeDir);
-  }
+  String? _pathOf(VolumeRelativeDirectory? dir) => dir != null ? pContext.join(dir.volumePath, dir.relativeDir) : null;
 
   @override
   void initState() {
@@ -82,15 +80,20 @@ class _ExplorerPageState extends State<ExplorerPage> {
 
   @override
   Widget build(BuildContext context) {
-    return ValueListenableBuilder<VolumeRelativeDirectory>(
+    return ValueListenableBuilder<VolumeRelativeDirectory?>(
       valueListenable: _directory,
       builder: (context, directory, child) {
-        final atRoot = directory.relativeDir.isEmpty;
+        final atRoot = directory?.relativeDir.isEmpty ?? true;
         return AvesPopScope(
           handlers: [
             APopHandler(
               canPop: (context) => atRoot,
-              onPopBlocked: (context) => _goTo(pContext.dirname(_currentDirectoryPath)),
+              onPopBlocked: (context) {
+                final path = _pathOf(directory);
+                if (path != null) {
+                  _goTo(pContext.dirname(path));
+                }
+              },
             ),
             tvNavigationPopHandler,
             doubleBackPopHandler,
@@ -118,7 +121,7 @@ class _ExplorerPageState extends State<ExplorerPage> {
                             AnimationLimiter(
                               // animation limiter should not be above the app bar
                               // so that the crumb line can automatically scroll
-                              key: ValueKey(_currentDirectoryPath),
+                              key: ValueKey(contents),
                               child: SliverList.builder(
                                 itemBuilder: (context, index) {
                                   return AnimationConfiguration.staggeredList(
@@ -147,18 +150,26 @@ class _ExplorerPageState extends State<ExplorerPage> {
                     ),
                   ),
                   const Divider(height: 0),
-                  SafeArea(
-                    top: false,
-                    bottom: true,
-                    child: Padding(
-                      padding: const EdgeInsets.all(8),
-                      child: AvesFilterChip(
-                        filter: PathFilter(_currentDirectoryPath),
-                        maxWidth: double.infinity,
-                        onTap: (filter) => _goToCollectionPage(context, filter),
-                        onLongPress: null,
-                      ),
-                    ),
+                  ValueListenableBuilder<VolumeRelativeDirectory?>(
+                    valueListenable: _contentsDirectory,
+                    builder: (context, contentsDirectory, child) {
+                      final dirPath = _pathOf(contentsDirectory);
+                      return dirPath != null
+                          ? SafeArea(
+                              top: false,
+                              bottom: true,
+                              child: Padding(
+                                padding: const EdgeInsets.all(8),
+                                child: AvesFilterChip(
+                                  filter: PathFilter(dirPath),
+                                  maxWidth: double.infinity,
+                                  onTap: (filter) => _goToCollectionPage(context, filter),
+                                  onLongPress: null,
+                                ),
+                              ),
+                            )
+                          : const SizedBox();
+                    },
                   ),
                 ],
               ),
@@ -177,15 +188,18 @@ class _ExplorerPageState extends State<ExplorerPage> {
         if (loading) {
           bottom = const CircularProgressIndicator();
         } else {
-          final source = context.read<CollectionSource>();
-          final album = _getAlbumPath(source, Directory(_currentDirectoryPath));
-          if (album != null) {
-            bottom = AvesFilterChip(
-              filter: AlbumFilter(album, source.getAlbumDisplayName(context, album)),
-              maxWidth: double.infinity,
-              onTap: (filter) => _goToCollectionPage(context, filter),
-              onLongPress: null,
-            );
+          final dirPath = _pathOf(_contentsDirectory.value);
+          if (dirPath != null) {
+            final source = context.read<CollectionSource>();
+            final album = _getAlbumPath(source, Directory(dirPath));
+            if (album != null) {
+              bottom = AvesFilterChip(
+                filter: AlbumFilter(album, source.getAlbumDisplayName(context, album)),
+                maxWidth: double.infinity,
+                onTap: (filter) => _goToCollectionPage(context, filter),
+                onLongPress: null,
+              );
+            }
           }
         }
 
@@ -249,11 +263,14 @@ class _ExplorerPageState extends State<ExplorerPage> {
   }
 
   void _updateContents() {
-    final contents = <Directory>[];
+    final directory = _directory.value;
+    final dirPath = _pathOf(directory);
+    if (dirPath == null) return;
 
+    final contents = <Directory>[];
     final source = context.read<CollectionSource>();
     final albums = source.rawAlbums.map((v) => v.toLowerCase()).toSet();
-    Directory(_currentDirectoryPath).list().listen((event) {
+    Directory(dirPath).list().listen((event) {
       final entity = event.absolute;
       if (entity is Directory) {
         final dirPath = entity.path.toLowerCase();
@@ -268,6 +285,7 @@ class _ExplorerPageState extends State<ExplorerPage> {
           final nameB = pContext.split(b.path).last;
           return compareAsciiUpperCaseNatural(nameA, nameB);
         });
+      _contentsDirectory.value = directory;
     });
   }
 

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

@@ -7,7 +7,7 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
 class CrumbLine extends StatefulWidget {
-  final VolumeRelativeDirectory directory;
+  final VolumeRelativeDirectory? directory;
   final void Function(String path) onTap;
 
   const CrumbLine({
@@ -25,7 +25,7 @@ class CrumbLine extends StatefulWidget {
 class _CrumbLineState extends State<CrumbLine> {
   final ScrollController _scrollController = ScrollController();
 
-  VolumeRelativeDirectory get directory => widget.directory;
+  VolumeRelativeDirectory? get directory => widget.directory;
 
   @override
   void dispose() {
@@ -36,7 +36,7 @@ class _CrumbLineState extends State<CrumbLine> {
   @override
   void didUpdateWidget(covariant CrumbLine oldWidget) {
     super.didUpdateWidget(oldWidget);
-    if (oldWidget.directory.relativeDir.length < widget.directory.relativeDir.length) {
+    if ((oldWidget.directory?.relativeDir.length ?? 0) < (widget.directory?.relativeDir.length ?? 0)) {
       // scroll to show last crumb
       WidgetsBinding.instance.addPostFrameCallback((_) {
         final animate = context.read<Settings>().animate;
@@ -56,10 +56,15 @@ class _CrumbLineState extends State<CrumbLine> {
 
   @override
   Widget build(BuildContext context) {
-    List<String> parts = [
-      directory.getVolumeDescription(context),
-      ...pContext.split(directory.relativeDir),
-    ];
+    final _directory = directory;
+    final parts = <String>[];
+    if (_directory != null) {
+      parts.addAll([
+        _directory.getVolumeDescription(context),
+        ...pContext.split(_directory.relativeDir),
+      ]);
+    }
+
     final crumbColor = DefaultTextStyle.of(context).style.color;
     return ListView.builder(
       scrollDirection: Axis.horizontal,
@@ -84,13 +89,15 @@ class _CrumbLineState extends State<CrumbLine> {
           );
         }
         return GestureDetector(
-          onTap: () {
-            final path = pContext.joinAll([
-              directory.volumePath,
-              ...parts.skip(1).take(index),
-            ]);
-            widget.onTap(path);
-          },
+          onTap: _directory != null
+              ? () {
+                  final path = pContext.joinAll([
+                    _directory.volumePath,
+                    ...parts.skip(1).take(index),
+                  ]);
+                  widget.onTap(path);
+                }
+              : null,
           child: Container(
             // use a `Container` with a dummy color to make it expand
             // so that we can also detect taps around the title `Text`