yx_virtual_device

---

A Flutter package for simulating different device screens during development. Test your responsive layouts on various device sizes without needing physical devices or multiple emulators.

It is important not to use it for release builds!!!

Features

• 📱 Simulate iOS, Android, and custom device screens
• 🔄 Hot-swap devices at runtime
• 📐 Accurate screen sizes, pixel ratios, and safe areas
• 🎨 Works with existing Flutter widgets (MediaQuery, LayoutBuilder, etc.)

Screenshots

Installation

dependencies:
  yx_virtual_device: ^1.0.0

Quick Start

1. Setup Bindings

Initialize the virtual device bindings before runApp:

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

void main() {
  VirtualDeviceDevtools.setup();
  runApp(const MyApp());
}

2. Switch Devices

Use VirtualDeviceDevtools.setDevice() to change the simulated device:

// Set a specific device
VirtualDeviceDevtools.setDevice(Devices.ios.iPhone13);

// Reset to real device
VirtualDeviceDevtools.setDevice(null);

Available Devices

Standard Devices

Devices.standard.w360p3   // 360×800 @3x
Devices.standard.w375p3   // 375×812 @3x
Devices.standard.w414p3   // 414×896 @3x
// ... and more

iOS Devices

Devices.ios.iPhone13
Devices.ios.iPhone13ProMax
Devices.ios.iPhoneSE
Devices.ios.iPadPro
// ... and more

Android Devices

Devices.android.samsungGalaxyS21
Devices.android.pixel5
Devices.android.onePlus9
// ... and more

Get All Devices

// All devices
final allDevices = Devices.all;

// By platform
final iosDevices = Devices.ios.all;
final androidDevices = Devices.android.all;
final standardDevices = Devices.standard.all;

Custom Devices

Create your own device configurations:

final myDevice = DeviceInfo(
  identifier: const DeviceIdentifier(
    TargetPlatform.android,
    DeviceType.phone,
    'my-custom-device',
  ),
  name: 'My Custom Device',
  pixelRatio: 3.0,
  screenSize: const Size(400, 800),
  safeAreas: const EdgeInsets.only(top: 44, bottom: 34),
  rotatedSafeAreas: const EdgeInsets.only(left: 44, right: 44),
);

VirtualDeviceDevtools.setDevice(myDevice);

Example

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

void main() {
  // Called before [runApp] to replace bindings.
  // It is good not to use it in the production.
  if (kProfileMode || kDebugMode) {
      VirtualDeviceDevtools.setup();
  }
  runApp(const MyApp());
}

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

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

class _MyAppState extends State<MyApp> {
  DeviceInfo? _currentDevice;

  void _setDevice(DeviceInfo? device) {
    setState(() {
      _currentDevice = device;
      VirtualDeviceDevtools.setDevice(device);
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(_currentDevice?.name ?? 'Real Device'),
        ),
        body: LayoutBuilder(
          builder: (context, constraints) {
            final mq = MediaQuery.of(context);
            return Center(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Text('Screen: ${mq.size.width.toInt()}×${mq.size.height.toInt()}'),
                  Text('Pixel Ratio: ${mq.devicePixelRatio}x'),
                  Text('Constraints: ${constraints.maxWidth.toInt()}×${constraints.maxHeight.toInt()}'),
                ],
              ),
            );
          },
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: () => _showDevicePicker(context),
          child: const Icon(Icons.devices),
        ),
      ),
    );
  }

  void _showDevicePicker(BuildContext context) {
    showModalBottomSheet(
      context: context,
      builder: (context) {
        final devices = <DeviceInfo?>[
          null,
          ...Devices.standard.all,
          ...Devices.ios.all.take(5),
          ...Devices.android.all.take(5),
        ];

        return ListView.builder(
          itemCount: devices.length,
          itemBuilder: (context, index) {
            final device = devices[index];
            return ListTile(
              leading: Icon(device == null ? Icons.phone_android : Icons.devices),
              title: Text(device?.name ?? 'Real Device'),
              subtitle: device != null
                  ? Text('${device.screenSize.width.toInt()}×${device.screenSize.height.toInt()} @${device.pixelRatio}x')
                  : null,
              selected: device?.name == _currentDevice?.name,
              onTap: () {
                _setDevice(device);
                Navigator.pop(context);
              },
            );
          },
        );
      },
    );
  }
}

Accessing Device Info

From Binding

final binding = VirtualWidgetsFlutterBinding.virtualBinding;
final currentDevice = binding.device;

From MediaQuery

final mq = MediaQuery.of(context);
print('Size: ${mq.size}');
print('Pixel Ratio: ${mq.devicePixelRatio}');
print('Padding: ${mq.padding}');

From View

final view = View.of(context);
print('Physical Size: ${view.physicalSize}');
print('Device Pixel Ratio: ${view.devicePixelRatio}');

API Reference

VirtualDeviceDevtools

Method	Description
setup()	Initialize virtual device bindings
setDevice(DeviceInfo?)	Set the current virtual device

DeviceInfo

Property	Type	Description
name	String	Display name
identifier	DeviceIdentifier	Unique identifier
screenSize	Size	Logical screen size
pixelRatio	double	Device pixel ratio
safeAreas	EdgeInsets	Safe area insets (portrait)
rotatedSafeAreas	EdgeInsets	Safe area insets (landscape)
frameSize	Size?	Device frame size (optional)
screenPath	Path?	Screen clip path (optional)

DeviceIdentifier

Property	Type	Description
platform	TargetPlatform	Target platform
type	DeviceType	Device type (phone, tablet, etc.)
id	String	Unique string identifier

Devices

Property	Type	Description
all	List<DeviceInfo>	All available devices
ios	IosDevices	iOS devices
android	AndroidDevices	Android devices
standard	StandardDevices	Standard screen sizes

Use Cases

• 📱 Responsive Testing - Test layouts on different screen sizes
• 🎨 Design Verification - Verify designs match specifications
• 📸 Screenshots - Generate screenshots for various devices
• 🐛 Bug Reproduction - Reproduce device-specific layout issues

License

MIT License