Handle cancellation pipeline properly for dir fetch

Also remove progress display for dir fetch, it currently doesn't work

Author: dvd-bnc

lib/backend/fetch.dart

@@ -9,25 +9,24 @@ import 'package:flutter/foundation.dart';
 enum SortType { name, modified, type, size }
 
 class CancelableFsFetch {
-  final fs.File source;
-  final ValueChanged<List<EntityInfo>?> onFetched;
-  final VoidCallback? onCancel;
-  final ValueChanged<double?>? onProgressChange;
-  final bool ascending;
-  final SortType sortType;
-  final bool showHidden;
-
   CancelableFsFetch({
     required this.source,
     required this.onFetched,
     this.onCancel,
-    this.onProgressChange,
     this.ascending = false,
     this.sortType = SortType.name,
     this.showHidden = false,
   });
 
+  final fs.File source;
+  final ValueChanged<List<EntityInfo>?> onFetched;
+  final VoidCallback? onCancel;
+  final bool ascending;
+  final SortType sortType;
+  final bool showHidden;
+
   final fs.Cancellable cancellable = fs.Cancellable();
+  final Completer<void> _cancellableCompleter = Completer();
 
   bool get cancelled => cancellable.isCancelled;
 
@@ -40,20 +39,23 @@ class CancelableFsFetch {
     );
     final enumerator = await enumeratorOp.result;
 
-    onProgressChange?.call(0.0);
-
-    // final directories = SortedList<EntityInfo>(
-    //   (a, b) => _sort(a, b, isDirectory: true)!,
-    // );
-    // final files = SortedList<EntityInfo>(
-    //   (a, b) => _sort(a, b, isDirectory: false)!,
-    // );
     final directories = <EntityInfo>[];
     final files = <EntityInfo>[];
 
     while (true) {
-      final enumerateOp = enumerator.enumerate(cancellable: cancellable);
-      final fileList = await enumerateOp.result;
+      final fs.FileList? fileList;
+      try {
+        final enumerateOp = enumerator.enumerate(cancellable: cancellable);
+        fileList = await enumerateOp.result;
+      } on fs.NativeException catch (e) {
+        // G_IO_CANCELLED
+        if (e.code == 19) {
+          _cancellableCompleter.complete();
+          return;
+        }
+
+        rethrow;
+      }
 
       if (fileList == null) break;
 
@@ -75,6 +77,9 @@ class CancelableFsFetch {
       }
       fileList.destroy();
     }
+
+    _cancellableCompleter.complete();
+
     directories.sort((a, b) => _sort(a, b, isDirectory: true)!);
     files.sort((a, b) => _sort(a, b, isDirectory: false)!);
 
@@ -112,10 +117,11 @@ class CancelableFsFetch {
     return null;
   }
 
-  void cancel() async {
+  Future<void> cancel() async {
     if (cancellable.isCancelled) return;
 
     cancellable.cancel();
+    return _cancellableCompleter.future;
   }
 }
 

lib/backend/workspace.dart

@@ -26,7 +26,6 @@ class WorkspaceController with ChangeNotifier {
   // Loading related
   late String _currentDir;
   List<EntityInfo>? _currentInfo;
-  double? _loadingProgress;
   OSError? _lastError;
 
   // Sort, view and selection
@@ -55,19 +54,15 @@ class WorkspaceController with ChangeNotifier {
   }
 
   Future<void> getInfoForDir(fs.File dir) async {
-    /* await */
-    _fetcher?.cancel();
+    await _fetcher?.cancel();
     _lastError = null;
+    _fetcher?.cancellable.destroy();
     _fetcher = CancelableFsFetch(
       source: dir,
       onFetched: (data) {
         _currentInfo = data;
         notifyListeners();
       },
-      onProgressChange: (value) {
-        _loadingProgress = value;
-        notifyListeners();
-      },
       showHidden: _showHidden,
       ascending: _ascending,
       sortType: _sortType,
@@ -77,7 +72,6 @@ class WorkspaceController with ChangeNotifier {
 
   List<EntityInfo>? get currentInfo =>
       _currentInfo != null ? List.unmodifiable(_currentInfo!) : null;
-  double? get loadingProgress => _loadingProgress;
 
   void clearCurrentInfo() {
     _currentInfo = null;

lib/widgets/breadcrumbs_bar.dart

@@ -13,7 +13,6 @@ class BreadcrumbsBar extends StatefulWidget {
     this.onPathSubmitted,
     this.leading,
     this.actions,
-    this.loadingProgress,
     super.key,
   });
 
@@ -22,7 +21,6 @@ class BreadcrumbsBar extends StatefulWidget {
   final ValueChanged<String>? onPathSubmitted;
   final List<Widget>? leading;
   final List<Widget>? actions;
-  final double? loadingProgress;
 
   @override
   State<BreadcrumbsBar> createState() => _BreadcrumbsBarState();
@@ -86,17 +84,14 @@ class _BreadcrumbsBarState extends State<BreadcrumbsBar> {
                           : BorderSide.none,
                     ),
                     clipBehavior: Clip.antiAlias,
-                    child: _LoadingIndicator(
-                      progress: widget.loadingProgress,
-                      child: GestureDetector(
-                        onTap: () {
-                          FocusScope.of(context).requestFocus(focusNode);
-                        },
-                        child: Container(
-                          height: double.infinity,
-                          alignment: AlignmentDirectional.centerStart,
-                          child: _guts,
-                        ),
+                    child: GestureDetector(
+                      onTap: () {
+                        FocusScope.of(context).requestFocus(focusNode);
+                      },
+                      child: Container(
+                        height: double.infinity,
+                        alignment: AlignmentDirectional.centerStart,
+                        child: _guts,
                       ),
                     ),
                   ),
@@ -219,94 +214,3 @@ class _BreadcrumbChip extends StatelessWidget {
     );
   }
 }
-
-class _LoadingIndicator extends StatefulWidget {
-  const _LoadingIndicator({required this.progress, required this.child});
-  final double? progress;
-  final Widget child;
-
-  @override
-  _LoadingIndicatorState createState() => _LoadingIndicatorState();
-}
-
-class _LoadingIndicatorState extends State<_LoadingIndicator>
-    with TickerProviderStateMixin {
-  late AnimationController fadeController;
-  late AnimationController progressController;
-
-  @override
-  void initState() {
-    super.initState();
-    fadeController = AnimationController(
-      vsync: this,
-      duration: const Duration(milliseconds: 250),
-      value: widget.progress != null ? 1 : 0,
-    );
-    progressController = AnimationController(
-      vsync: this,
-      duration: const Duration(milliseconds: 150),
-      value: widget.progress,
-    );
-  }
-
-  @override
-  void dispose() {
-    fadeController.dispose();
-    progressController.dispose();
-    super.dispose();
-  }
-
-  @override
-  void didUpdateWidget(covariant _LoadingIndicator old) {
-    super.didUpdateWidget(old);
-
-    _updateController(old);
-  }
-
-  Future<void> _updateController(_LoadingIndicator old) async {
-    if (widget.progress != old.progress) {
-      if (widget.progress != null && old.progress == null) {
-        fadeController.value = 1;
-        await progressController.animateTo(widget.progress!);
-      } else if (widget.progress == null && old.progress != null) {
-        await fadeController.reverse();
-        progressController.value = 0;
-      } else if (widget.progress != null && old.progress != null) {
-        if (widget.progress! > old.progress!) {
-          await progressController.animateTo(widget.progress!);
-        } else if (widget.progress! < old.progress!) {
-          await progressController.animateBack(widget.progress!);
-        }
-      }
-    }
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return AnimatedBuilder(
-      animation: Listenable.merge([progressController, fadeController]),
-      builder: (context, child) {
-        return Stack(
-          children: [
-            child!,
-            Positioned.directional(
-              textDirection: Directionality.of(context),
-              top: 12,
-              bottom: 12,
-              end: 12,
-              width: 16,
-              child: FadeTransition(
-                opacity: fadeController,
-                child: CircularProgressIndicator(
-                  value: progressController.value,
-                  strokeWidth: 2,
-                ),
-              ),
-            ),
-          ],
-        );
-      },
-      child: widget.child,
-    );
-  }
-}

lib/widgets/workspace.dart

@@ -448,7 +448,6 @@ class _WorkspaceTopbar extends StatelessWidget {
             },
           ),
       ],
-      loadingProgress: controller.loadingProgress,
     );
   }