[file_selector] Add getDirectoryPaths implementation for Windows (#3704)

Part of flutter/flutter#74323

packages/file_selector/file_selector_windows/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.9.2
+
+* Adds `getDirectoryPaths` implementation.
+
 ## 0.9.1+8
 
 * Sets a cmake_policy compatibility version to fix build warnings.

packages/file_selector/file_selector_windows/example/lib/get_multiple_directories_page.dart

@@ -0,0 +1,86 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:file_selector_platform_interface/file_selector_platform_interface.dart';
+import 'package:flutter/material.dart';
+
+/// Screen that allows the user to select one or more directories using `getDirectoryPaths`,
+/// then displays the selected directories in a dialog.
+class GetMultipleDirectoriesPage extends StatelessWidget {
+  /// Default Constructor
+  const GetMultipleDirectoriesPage({super.key});
+
+  Future<void> _getDirectoryPaths(BuildContext context) async {
+    const String confirmButtonText = 'Choose';
+    final List<String?> directoriesPaths =
+        await FileSelectorPlatform.instance.getDirectoryPaths(
+      confirmButtonText: confirmButtonText,
+    );
+    if (directoriesPaths.isEmpty) {
+      // Operation was canceled by the user.
+      return;
+    }
+    if (context.mounted) {
+      await showDialog<void>(
+        context: context,
+        builder: (BuildContext context) =>
+            TextDisplay(directoriesPaths.join('\n')),
+      );
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Select multiple directories'),
+      ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            ElevatedButton(
+              style: ElevatedButton.styleFrom(
+                // ignore: deprecated_member_use
+                primary: Colors.blue,
+                // ignore: deprecated_member_use
+                onPrimary: Colors.white,
+              ),
+              child: const Text(
+                  'Press to ask user to choose multiple directories'),
+              onPressed: () => _getDirectoryPaths(context),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// Widget that displays a text file in a dialog.
+class TextDisplay extends StatelessWidget {
+  /// Creates a `TextDisplay`.
+  const TextDisplay(this.directoryPaths, {super.key});
+
+  /// The paths selected in the dialog.
+  final String directoryPaths;
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: const Text('Selected Directories'),
+      content: Scrollbar(
+        child: SingleChildScrollView(
+          child: Text(directoryPaths),
+        ),
+      ),
+      actions: <Widget>[
+        TextButton(
+          child: const Text('Close'),
+          onPressed: () => Navigator.pop(context),
+        ),
+      ],
+    );
+  }
+}

packages/file_selector/file_selector_windows/example/lib/home_page.dart

@@ -55,6 +55,13 @@ class HomePage extends StatelessWidget {
               child: const Text('Open a get directory dialog'),
               onPressed: () => Navigator.pushNamed(context, '/directory'),
             ),
+            const SizedBox(height: 10),
+            ElevatedButton(
+              style: style,
+              child: const Text('Open a get directories dialog'),
+              onPressed: () =>
+                  Navigator.pushNamed(context, '/multi-directories'),
+            ),
           ],
         ),
       ),

packages/file_selector/file_selector_windows/example/lib/main.dart

@@ -5,6 +5,7 @@
 import 'package:flutter/material.dart';
 
 import 'get_directory_page.dart';
+import 'get_multiple_directories_page.dart';
 import 'home_page.dart';
 import 'open_image_page.dart';
 import 'open_multiple_images_page.dart';
@@ -36,6 +37,8 @@ class MyApp extends StatelessWidget {
         '/open/text': (BuildContext context) => const OpenTextPage(),
         '/save/text': (BuildContext context) => SaveTextPage(),
         '/directory': (BuildContext context) => const GetDirectoryPage(),
+        '/multi-directories': (BuildContext context) =>
+            const GetMultipleDirectoriesPage()
       },
     );
   }

packages/file_selector/file_selector_windows/example/pubspec.yaml

@@ -8,7 +8,7 @@ environment:
   flutter: ">=3.3.0"
 
 dependencies:
-  file_selector_platform_interface: ^2.2.0
+  file_selector_platform_interface: ^2.4.0
   file_selector_windows:
     # When depending on this package from a real application you should use:
     #   file_selector_windows: ^x.y.z

packages/file_selector/file_selector_windows/lib/file_selector_windows.dart

@@ -83,6 +83,22 @@ class FileSelectorWindows extends FileSelectorPlatform {
         confirmButtonText);
     return paths.isEmpty ? null : paths.first!;
   }
+
+  @override
+  Future<List<String>> getDirectoryPaths({
+    String? initialDirectory,
+    String? confirmButtonText,
+  }) async {
+    final List<String?> paths = await _hostApi.showOpenDialog(
+        SelectionOptions(
+          allowMultiple: true,
+          selectFolders: true,
+          allowedTypes: <TypeGroup>[],
+        ),
+        initialDirectory,
+        confirmButtonText);
+    return paths.isEmpty ? <String>[] : List<String>.from(paths);
+  }
 }
 
 List<TypeGroup> _typeGroupsFromXTypeGroups(List<XTypeGroup>? xtypes) {

packages/file_selector/file_selector_windows/pubspec.yaml

@@ -2,7 +2,7 @@ name: file_selector_windows
 description: Windows implementation of the file_selector plugin.
 repository: https://github.com/flutter/packages/tree/main/packages/file_selector/file_selector_windows
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+file_selector%22
-version: 0.9.1+8
+version: 0.9.2
 
 environment:
   sdk: ">=2.18.0 <4.0.0"
@@ -18,7 +18,7 @@ flutter:
 
 dependencies:
   cross_file: ^0.3.1
-  file_selector_platform_interface: ^2.2.0
+  file_selector_platform_interface: ^2.4.0
   flutter:
     sdk: flutter
 

packages/file_selector/file_selector_windows/test/file_selector_windows_test.dart

@@ -213,6 +213,37 @@ void main() {
     });
   });
 
+  group('#getDirectoryPaths', () {
+    setUp(() {
+      when(mockApi.showOpenDialog(any, any, any))
+          .thenReturn(<String?>['foo', 'bar']);
+    });
+
+    test('simple call works', () async {
+      final List<String?> paths = await plugin.getDirectoryPaths();
+
+      expect(paths[0], 'foo');
+      expect(paths[1], 'bar');
+      final VerificationResult result =
+          verify(mockApi.showOpenDialog(captureAny, null, null));
+      final SelectionOptions options = result.captured[0] as SelectionOptions;
+      expect(options.allowMultiple, true);
+      expect(options.selectFolders, true);
+    });
+
+    test('passes initialDirectory correctly', () async {
+      await plugin.getDirectoryPath(initialDirectory: '/example/directory');
+
+      verify(mockApi.showOpenDialog(any, '/example/directory', null));
+    });
+
+    test('passes confirmButtonText correctly', () async {
+      await plugin.getDirectoryPath(confirmButtonText: 'Open Directory');
+
+      verify(mockApi.showOpenDialog(any, null, 'Open Directory'));
+    });
+  });
+
   group('#getSavePath', () {
     setUp(() {
       when(mockApi.showSaveDialog(any, any, any, any))

packages/file_selector/file_selector_windows/windows/test/file_selector_plugin_test.cpp

@@ -420,6 +420,55 @@ TEST(FileSelectorPlugin, TestGetDirectorySimple) {
   EXPECT_EQ(std::get<std::string>(paths[0]), "C:\\Program Files");
 }
 
+TEST(FileSelectorPlugin, TestGetDirectoryMultiple) {
+  const HWND fake_window = reinterpret_cast<HWND>(1337);
+  // These are actual files, but since the plugin implementation doesn't
+  // validate the types of items returned from the system dialog, they are fine
+  // to use for unit tests.
+  ScopedTestFileIdList fake_selected_dir_1;
+  ScopedTestFileIdList fake_selected_dir_2;
+  LPCITEMIDLIST fake_selected_dirs[] = {
+      fake_selected_dir_1.file(),
+      fake_selected_dir_2.file(),
+  };
+  IShellItemArrayPtr fake_result_array;
+  ::SHCreateShellItemArrayFromIDLists(2, fake_selected_dirs,
+                                      &fake_result_array);
+
+  bool shown = false;
+  MockShow show_validator = [&shown, fake_result_array, fake_window](
+                                const TestFileDialogController& dialog,
+                                HWND parent) {
+    shown = true;
+    EXPECT_EQ(parent, fake_window);
+
+    // Validate options.
+    FILEOPENDIALOGOPTIONS options;
+    dialog.GetOptions(&options);
+    EXPECT_NE(options & FOS_ALLOWMULTISELECT, 0U);
+    EXPECT_NE(options & FOS_PICKFOLDERS, 0U);
+
+    return MockShowResult(fake_result_array);
+  };
+
+  FileSelectorPlugin plugin(
+      [fake_window] { return fake_window; },
+      std::make_unique<TestFileDialogControllerFactory>(show_validator));
+  ErrorOr<EncodableList> result = plugin.ShowOpenDialog(
+      CreateOptions(AllowMultipleArg(true), SelectFoldersArg(true),
+                    EncodableList()),
+      nullptr, nullptr);
+
+  EXPECT_TRUE(shown);
+  ASSERT_FALSE(result.has_error());
+  const EncodableList& paths = result.value();
+  EXPECT_EQ(paths.size(), 2);
+  EXPECT_EQ(std::get<std::string>(paths[0]),
+            Utf8FromUtf16(fake_selected_dir_1.path()));
+  EXPECT_EQ(std::get<std::string>(paths[1]),
+            Utf8FromUtf16(fake_selected_dir_2.path()));
+}
+
 TEST(FileSelectorPlugin, TestGetDirectoryCancel) {
   const HWND fake_window = reinterpret_cast<HWND>(1337);