windows_file_picker_wrapper

A rock-solid, deadlock-free native Windows 10/11 File and Folder Picker for Flutter Desktop applications.

Why this package?

Existing Flutter Windows picker plugins (file_picker, file_selector_windows) invoke the synchronous Win32 IFileDialog::Show(HWND) API directly on Flutter's platform thread. This leads to well-known bugs on Windows:

  • Focus Drop / Hidden Dialogs: On repeated calls, Windows places the dialog behind the active DirectX/OpenGL rendering window.
  • COM Deadlocks: Cross-apartment proxy contention with background workers / DirectML / ONNX runtimes freezes the main message loop.
  • Main Thread UI Freezes: The Flutter UI thread locks up while the modal dialog is open.

windows_file_picker_wrapper solves this by spawning native Windows 10/11 Explorer dialogs in an isolated native Windows subprocess (-STA).

Benefits:

  • 100% Native Windows 10/11 UI: Uses the modern IFileOpenDialog (FOS_PICKFOLDERS), OpenFileDialog, and SaveFileDialog.
  • Always in Foreground: Windows OS gives top-level foreground focus to the dialog window automatically.
  • Non-blocking: Flutter UI keeps rendering smoothly at 60/120 FPS.
  • 100% Reliable: Open/close pickers 1,000 times consecutively without a single hang or freeze.

Installation

Add to your pubspec.yaml:

dependencies:
  windows_file_picker_wrapper: ^1.0.2

Usage

1. Modern Folder Picker

import 'package:windows_file_picker_wrapper/windows_file_picker_wrapper.dart';

final String? folderPath = await WindowsFilePickerWrapper.pickFolder(
  title: 'Select Image Directory',
  initialDirectory: r'C:\Photos',
);

2. Multi-File Picker

final List<String>? files = await WindowsFilePickerWrapper.pickFiles(
  title: 'Select Images',
  type: WindowsFileType.image,
  allowMultiple: true,
);

3. Single File Picker

final String? filePath = await WindowsFilePickerWrapper.pickFile(
  title: 'Select Document',
  type: WindowsFileType.custom,
  allowedExtensions: ['pdf', 'docx', 'xlsx'],
);

4. Save File Dialog

final String? savePath = await WindowsFilePickerWrapper.saveFile(
  title: 'Save Backup',
  fileName: 'backup_2026.json',
  allowedExtensions: ['json'],
);

Example App

See the example directory for a complete iOS Cupertino-styled demo application.

License

MIT License

Libraries

windows_file_picker_wrapper
A rock-solid, high-performance native Windows File and Folder Picker for Flutter desktop. Uses modern Windows 10/11 COM Common Item Dialogs (IFileOpenDialog / IFileSaveDialog) and classic Win32 APIs via dart:ffi in worker isolates for instantaneous response.