feat(windows): add parentWindowHandle parameter to override window handle lookup

lib/src/file_picker.dart

@@ -87,6 +87,7 @@ abstract final class FilePicker {
     bool readSequential = false,
     bool cancelUploadOnWindowBlur = true,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) {
     return FilePickerPlatform.instance.pickFiles(
       dialogTitle: dialogTitle,
@@ -102,6 +103,7 @@ abstract final class FilePicker {
       readSequential: readSequential,
       cancelUploadOnWindowBlur: cancelUploadOnWindowBlur,
       androidSafOptions: androidSafOptions,
+      parentWindowHandle: parentWindowHandle,
     );
   }
 
@@ -221,12 +223,14 @@ abstract final class FilePicker {
     bool lockParentWindow = false,
     String? initialDirectory,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) {
     return FilePickerPlatform.instance.getDirectoryPath(
       dialogTitle: dialogTitle,
       lockParentWindow: lockParentWindow,
       initialDirectory: initialDirectory,
       androidSafOptions: androidSafOptions,
+      parentWindowHandle: parentWindowHandle,
     );
   }
 
@@ -272,6 +276,7 @@ abstract final class FilePicker {
     required Uint8List bytes,
     Function(FilePickerStatus)? onFileLoading,
     bool lockParentWindow = false,
+    int? parentWindowHandle,
   }) {
     return FilePickerPlatform.instance.saveFile(
       dialogTitle: dialogTitle,
@@ -282,6 +287,7 @@ abstract final class FilePicker {
       bytes: bytes,
       onFileLoading: onFileLoading,
       lockParentWindow: lockParentWindow,
+      parentWindowHandle: parentWindowHandle,
     );
   }
 

lib/src/platform/file_picker_platform_interface.dart

@@ -43,6 +43,7 @@ abstract class FilePickerPlatform extends PlatformInterface {
     bool readSequential = false,
     bool cancelUploadOnWindowBlur = true,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) async {
     throw UnimplementedError('pickFiles() has not been implemented.');
   }
@@ -76,6 +77,7 @@ abstract class FilePickerPlatform extends PlatformInterface {
     bool lockParentWindow = false,
     String? initialDirectory,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) async {
     throw UnimplementedError('getDirectoryPath() has not been implemented.');
   }
@@ -91,6 +93,7 @@ abstract class FilePickerPlatform extends PlatformInterface {
     required Uint8List bytes,
     Function(FilePickerStatus)? onFileLoading,
     bool lockParentWindow = false,
+    int? parentWindowHandle,
   }) async {
     throw UnimplementedError('saveFile() has not been implemented.');
   }

lib/src/platform/windows/file_picker_windows.dart

@@ -38,6 +38,7 @@ class FilePickerWindows extends FilePickerPlatform {
     int compressionQuality = 0,
     bool cancelUploadOnWindowBlur = true,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) async {
     final port = ReceivePort();
     await Isolate.spawn(
@@ -50,6 +51,7 @@ class FilePickerWindows extends FilePickerPlatform {
         allowedExtensions: allowedExtensions,
         allowMultiple: allowMultiple,
         lockParentWindow: lockParentWindow,
+        parentWindowHandle: parentWindowHandle,
       ),
     );
     final fileNames = (await port.first) as List<String>?;
@@ -104,18 +106,21 @@ class FilePickerWindows extends FilePickerPlatform {
     bool lockParentWindow = false,
     String? initialDirectory,
     AndroidSAFOptions? androidSafOptions,
+    int? parentWindowHandle,
   }) async {
     return compute(_getDirectoryPathIsolate, {
       'dialogTitle': dialogTitle,
       'initialDirectory': initialDirectory,
       'lockParentWindow': lockParentWindow,
+      'parentWindowHandle': parentWindowHandle,
     });
   }
 
   String? _getDirectoryPathIsolate(Map<String, Object?> args) {
     String? dialogTitle = args['dialogTitle'] as String?;
     String? initialDirectory = args['initialDirectory'] as String?;
     bool lockParentWindow = args['lockParentWindow'] as bool? ?? false;
+    int? parentWindowHandle = args['parentWindowHandle'] as int?;
 
     final hr = CoInitializeEx(
       COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE,
@@ -151,7 +156,13 @@ class FilePickerWindows extends FilePickerPlatform {
         }
 
         try {
-          fileDialog.show(lockParentWindow ? GetForegroundWindow() : null);
+          fileDialog.show(
+            lockParentWindow
+                ? (parentWindowHandle != null
+                    ? parentWindowHandle
+                    : GetForegroundWindow())
+                : null,
+          );
         } on WindowsException catch (e) {
           if (e.hr == HRESULT_FROM_WIN32(ERROR_CANCELLED)) {
             return null;
@@ -187,6 +198,7 @@ class FilePickerWindows extends FilePickerPlatform {
     required Uint8List bytes,
     Function(FilePickerStatus)? onFileLoading,
     bool lockParentWindow = false,
+    int? parentWindowHandle,
   }) async {
     final port = ReceivePort();
     await Isolate.spawn(
@@ -200,6 +212,7 @@ class FilePickerWindows extends FilePickerPlatform {
         allowedExtensions: allowedExtensions,
         lockParentWindow: lockParentWindow,
         confirmOverwrite: true,
+        parentWindowHandle: parentWindowHandle,
       ),
     );
     final savedFilePath = (await port.first) as String?;
@@ -336,7 +349,9 @@ class FilePickerWindows extends FilePickerPlatform {
         ofnExplorer | ofnFileMustExist | ofnHideReadOnly | ofnNoChangeDir;
 
     if (args.lockParentWindow) {
-      openFileNameW.ref.hwndOwner = _getWindowHandle();
+      openFileNameW.ref.hwndOwner = args.parentWindowHandle != null
+          ? Pointer.fromAddress(args.parentWindowHandle!)
+          : _getWindowHandle();
     }
 
     if (args.allowMultiple) {
@@ -412,6 +427,7 @@ class _OpenSaveFileArgs {
   final bool allowMultiple;
   final bool lockParentWindow;
   final bool confirmOverwrite;
+  final int? parentWindowHandle;
 
   _OpenSaveFileArgs({
     required this.port,
@@ -423,5 +439,6 @@ class _OpenSaveFileArgs {
     this.allowMultiple = false,
     this.lockParentWindow = false,
     this.confirmOverwrite = false,
+    this.parentWindowHandle,
   });
 }