files: Implement selections using shift key

lib/backend/entity_selector.dart

@@ -0,0 +1,83 @@
+import 'package:files/backend/entity_info.dart';
+import 'package:files/backend/workspace.dart';
+import 'package:flutter/services.dart';
+
+enum EntitySelectionMode {
+  single,
+  multiple,
+  none,
+  mixed;
+
+  factory EntitySelectionMode.fromKeys(Set<LogicalKeyboardKey> keys) {
+    final hasShiftKey = keys.contains(LogicalKeyboardKey.shiftLeft) ||
+        keys.contains(LogicalKeyboardKey.shiftRight);
+    final hasControlKey = keys.contains(LogicalKeyboardKey.controlLeft) ||
+        keys.contains(LogicalKeyboardKey.controlRight);
+
+    if (hasShiftKey && hasControlKey) {
+      return mixed;
+    }
+
+    if (hasControlKey) {
+      return single;
+    }
+
+    if (hasShiftKey) {
+      return multiple;
+    }
+
+    return none;
+  }
+}
+
+class EntitySelector {
+  final WorkspaceController _controller;
+  final EntityInfo _entity;
+  final EntitySelectionMode _mode;
+
+  EntitySelector(this._controller, this._entity, this._mode);
+
+  void perform() {
+    switch (_mode) {
+      case EntitySelectionMode.single:
+        _toggleEntitySelection();
+        _controller.lastClickedEntityIndex = _getEntityIndex();
+        break;
+      case EntitySelectionMode.multiple:
+        _controller.clearSelectedItems();
+        _extendSelectionToEntity();
+        break;
+      case EntitySelectionMode.mixed:
+        _extendSelectionToEntity();
+        break;
+      default:
+        _controller.clearSelectedItems();
+        _controller.addSelectedItem(_entity);
+        _controller.lastClickedEntityIndex = _getEntityIndex();
+    }
+  }
+
+  void _toggleEntitySelection() {
+    if (_controller.selectedItems.contains(_entity)) {
+      _controller.removeSelectedItem(_entity);
+    } else {
+      _controller.addSelectedItem(_entity);
+    }
+  }
+
+  void _extendSelectionToEntity() {
+    final entityIndex = _getEntityIndex();
+    final lastSelectedEntityIndex = _controller.lastClickedEntityIndex;
+    final entities = entityIndex < lastSelectedEntityIndex
+        ? _controller.currentInfo!
+            .sublist(entityIndex, lastSelectedEntityIndex + 1)
+        : _controller.currentInfo!
+            .sublist(lastSelectedEntityIndex, entityIndex + 1);
+
+    _controller.addSelectedItems(entities);
+  }
+
+  int _getEntityIndex() {
+    return _controller.currentInfo!.indexOf(_entity);
+  }
+}

lib/backend/workspace.dart

@@ -34,6 +34,7 @@ class WorkspaceController with ChangeNotifier {
   SortType _sortType = SortType.name;
   WorkspaceView _view = WorkspaceView.table; // save on SharedPreferences?
   final List<EntityInfo> _selectedItems = [];
+  int lastClickedEntityIndex = 0;
 
   // States
   late TableViewState _tableState;
@@ -130,6 +131,11 @@ class WorkspaceController with ChangeNotifier {
     notifyListeners();
   }
 
+  void addSelectedItems(Iterable<EntityInfo> infos) {
+    _selectedItems.addAll(infos);
+    notifyListeners();
+  }
+
   void removeSelectedItem(EntityInfo info) {
     _selectedItems.remove(info);
     notifyListeners();
@@ -140,6 +146,12 @@ class WorkspaceController with ChangeNotifier {
     notifyListeners();
   }
 
+  void resetSelection() {
+    lastClickedEntityIndex = 0;
+    _selectedItems.clear();
+    notifyListeners();
+  }
+
   List<String> get history => List.from(_history);
   int get historyOffset => _historyOffset;
 
@@ -163,7 +175,7 @@ class WorkspaceController with ChangeNotifier {
     }
 
     clearCurrentInfo();
-    clearSelectedItems();
+    resetSelection();
     await _directoryStream?.cancel();
     await getInfoForDir(Directory(newDir));
     _directoryStream =

lib/widgets/grid.dart

@@ -48,7 +48,7 @@ class _FilesGridState extends State<FilesGrid> {
     final WorkspaceController controller = WorkspaceController.of(context);
 
     return GestureDetector(
-      onTap: controller.clearSelectedItems,
+      onTap: controller.resetSelection,
       child: Scrollbar(
         controller: scrollController,
         child: GridView.builder(

lib/widgets/table.dart

@@ -56,7 +56,7 @@ class FilesTable extends StatelessWidget {
     return LayoutBuilder(
       builder: (context, constraints) {
         return GestureDetector(
-          onTap: () => controller.clearSelectedItems(),
+          onTap: () => controller.resetSelection(),
           child: DoubleScrollbars(
             horizontalController: horizontalController,
             verticalController: verticalController,

lib/widgets/workspace.dart

@@ -3,6 +3,7 @@ import 'dart:io';
 
 import 'package:collection/collection.dart';
 import 'package:files/backend/entity_info.dart';
+import 'package:files/backend/entity_selector.dart';
 import 'package:files/backend/fetch.dart';
 import 'package:files/backend/path_parts.dart';
 import 'package:files/backend/utils.dart';
@@ -135,25 +136,15 @@ class _FilesWorkspaceState extends State<FilesWorkspace> {
   }
 
   void _onEntityTap(EntityInfo entity) {
-    final bool selected = controller.selectedItems.contains(entity);
-    final Set<LogicalKeyboardKey> keysPressed =
-        RawKeyboard.instance.keysPressed;
-    final bool multiSelect = keysPressed.contains(
-          LogicalKeyboardKey.controlLeft,
-        ) ||
-        keysPressed.contains(
-          LogicalKeyboardKey.controlRight,
-        );
-
-    if (!multiSelect) controller.clearSelectedItems();
+    final selectionMode = EntitySelectionMode.fromKeys(
+      HardwareKeyboard.instance.logicalKeysPressed,
+    );
 
-    if (!selected && multiSelect) {
-      controller.addSelectedItem(entity);
-    } else if (selected && multiSelect) {
-      controller.removeSelectedItem(entity);
-    } else {
-      controller.addSelectedItem(entity);
-    }
+    EntitySelector(
+      controller,
+      entity,
+      selectionMode,
+    ).perform();
 
     setState(() {});
   }
@@ -263,7 +254,7 @@ class _FilesWorkspaceState extends State<FilesWorkspace> {
         SizedBox(
           height: 32,
           child: Material(
-            color: Theme.of(context).colorScheme.background,
+            color: Theme.of(context).colorScheme.surface,
             child: Padding(
               padding: const EdgeInsets.symmetric(horizontal: 8),
               child: Row(
@@ -299,7 +290,7 @@ class _FilesWorkspaceState extends State<FilesWorkspace> {
             Text(
               "This Folder is Empty",
               style: TextStyle(fontSize: 17),
-            )
+            ),
           ],
         ),
       );

pubspec.lock

@@ -133,10 +133,10 @@ packages:
     dependency: "direct main"
     description:
       name: collection
-      sha256: "4a07be6cb69c84d677a6c3096fcf960cc3285a8330b4603e0d463d15d9bd934c"
+      sha256: ee67cb0715911d28db6bf4af1026078bd6f0128b07a5f66fb2ed94ec6783c09a
       url: "https://pub.dev"
     source: hosted
-    version: "1.17.1"
+    version: "1.18.0"
   convert:
     dependency: transitive
     description:
@@ -343,10 +343,10 @@ packages:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: d92141dc6fe1dad30722f9aa826c7fbc896d021d792f80678280601aff8cf724
+      sha256: "0e0a020085b65b6083975e499759762399b4475f766c21668c4ecca34ea74e5a"
       url: "https://pub.dev"
     source: hosted
-    version: "0.2.0"
+    version: "0.8.0"
   material_design_icons_flutter:
     dependency: "direct main"
     description:
@@ -359,10 +359,10 @@ packages:
     dependency: transitive
     description:
       name: meta
-      sha256: "12307e7f0605ce3da64cf0db90e5fcab0869f3ca03f76be6bb2991ce0a55e82b"
+      sha256: "7687075e408b093f36e6bbf6c91878cc0d4cd10f409506f7bc996f68220b9136"
       url: "https://pub.dev"
     source: hosted
-    version: "1.9.0"
+    version: "1.12.0"
   mime:
     dependency: "direct main"
     description:
@@ -746,5 +746,5 @@ packages:
     source: hosted
     version: "3.1.1"
 sdks:
-  dart: ">=3.0.0-134.0.dev <4.0.0"
+  dart: ">=3.3.0-0 <4.0.0"
   flutter: ">=3.3.0"