Window Resize Border

A Flutter plugin that enhances window resizing experience on Windows by enlarging the resize border area, making it easier for users to grab and resize windows.

Features

• Enlarge window resize borders beyond Windows default size
• Customizable border width
• Easy to enable/disable at runtime
• Works on Windows 7, 8, 10, and 11

Platform Support

Windows	macOS	Linux	Web	Android	iOS
✅	❌	❌	❌	❌	❌

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  window_resize_border: ^0.1.0

Then run:

flutter pub get

Usage

Import the package:

import 'package:window_resize_border/window_resize_border.dart';

Create an instance of the plugin:

final windowResizeBorder = WindowResizeBorder();

Enable Enlarged Borders

Enable the enlarged borders with the default width (8 pixels):

await windowResizeBorder.enableEnlargedBorders();

Or specify a custom border width:

await windowResizeBorder.enableEnlargedBorders(borderWidth: 12);

Disable Enlarged Borders

Return to system default border size:

await windowResizeBorder.disableEnlargedBorders();

Complete Example

import 'package:flutter/material.dart';
import 'package:window_resize_border/window_resize_border.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final _windowResizeBorderPlugin = WindowResizeBorder();
  bool _enlargedBordersEnabled = false;
  int _borderWidth = 8;

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Window Resize Border Example'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Text(
                'Enlarged borders are ${_enlargedBordersEnabled ? 'enabled' : 'disabled'}',
                style: const TextStyle(fontSize: 18),
              ),
              const SizedBox(height: 20),
              if (_enlargedBordersEnabled)
                Slider(
                  value: _borderWidth.toDouble(),
                  min: 1,
                  max: 20,
                  divisions: 19,
                  label: _borderWidth.toString(),
                  onChanged: (value) {
                    setState(() {
                      _borderWidth = value.toInt();
                    });
                    _windowResizeBorderPlugin.enableEnlargedBorders(
                      borderWidth: _borderWidth,
                    );
                  },
                ),
              const SizedBox(height: 20),
              ElevatedButton(
                onPressed: () async {
                  bool success;
                  if (_enlargedBordersEnabled) {
                    success = await _windowResizeBorderPlugin.disableEnlargedBorders();
                  } else {
                    success = await _windowResizeBorderPlugin.enableEnlargedBorders(
                      borderWidth: _borderWidth,
                    );
                  }
                  
                  if (success) {
                    setState(() {
                      _enlargedBordersEnabled = !_enlargedBordersEnabled;
                    });
                  }
                },
                child: Text(
                  _enlargedBordersEnabled ? 'Disable Enlarged Borders' : 'Enable Enlarged Borders',
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

How It Works

This plugin uses Windows API to intercept the WM_NCHITTEST message and modify the hit-testing behavior of window borders. By extending the hit-test area beyond the visible border, it makes it easier for users to grab and resize the window.

Troubleshooting

Plugin not working

Make sure you're running your Flutter app on a Windows system. This plugin only works on Windows and will have no effect on other platforms.

Borders not expanding

If enabling the enlarged borders doesn't seem to have an effect, check:

1. You're running on Windows OS
2. Your app has a resizable window
3. Your Flutter app is using the Windows embedding correctly

Limitations

• Only works on Windows platforms
• Requires Flutter desktop support to be enabled
• Window appearance doesn't change, only the interactive area increases

Contributing

Contributions are welcome! If you have a bug fix or feature addition, please create a pull request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.