Native Device Kit #

A production-grade Flutter plugin that provides a unified, high-performance API to access native hardware features on Android and iOS. This plugin abstracts complex platform-specific implementations (Kotlin/Swift) into simple, clean Dart interfaces.

Features #

• Bluetooth (BLE): Scan for devices, connect/disconnect, read services, and stream events.
• NFC: Read and write NDEF tags with background tag discovery.
• USB: List connected USB devices and manage communication (supports Android USB Host & iOS External Accessory).
• Hardware Bridge: A flexible bridge to invoke any third-party native SDK method dynamically.

Installation #

Add native_device_kit as a dependency in your pubspec.yaml file.

dependencies:
  native_device_kit:
    path: ./native_device_kit  # If local, or use git/pub version

Platform Configuration #

Android #

Add the following permissions to your android/app/src/main/AndroidManifest.xml:

<manifest ...>
    <!-- Bluetooth Permissions -->
    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    
    <!-- NFC Permissions -->
    <uses-permission android:name="android.permission.NFC" />
    <uses-feature android:name="android.hardware.nfc" android:required="false" />

    <!-- USB Permissions -->
    <uses-feature android:name="android.hardware.usb.host" android:required="false" />
</manifest>

iOS #

Add the following keys to your ios/Runner/Info.plist to explain why you need these permissions:

<dict>
    <!-- Bluetooth Usage Description -->
    <key>NSBluetoothAlwaysUsageDescription</key>
    <string>Need Bluetooth to scan for and connect to supported devices.</string>
    <key>NSBluetoothPeripheralUsageDescription</key>
    <string>Need Bluetooth to connect to supported devices.</string>

    <!-- NFC Usage Description -->
    <key>NFCReaderUsageDescription</key>
    <string>Need NFC to read and write tags.</string>
    
    <!-- USB / External Accessory (if applicable) -->
    <key>UISupportsDocumentBrowser</key>
    <true/>
</dict>

Usage #

The plugin exposes a singleton instance NativeDeviceKit.instance which provides access to all modules.

1. Bluetooth Module #

import 'package:native_device_kit/native_device_kit.dart';

// Access the Bluetooth module
final bluetooth = NativeDeviceKit.instance.bluetooth;

// 1. Listen for events (Scan results, connection status)
bluetooth.eventStream.listen((event) {
  print("Bluetooth Event: $event");
});

// 2. Start Scanning
try {
  await bluetooth.scan();
} catch (e) {
  print("Scan Error: $e");
}

// 3. Connect to a device
await bluetooth.connect("DEVICE_ID_OR_UUID");

// 4. Disconnect
await bluetooth.disconnect("DEVICE_ID_OR_UUID");

2. NFC Module #

import 'package:native_device_kit/native_device_kit.dart';

final nfc = NativeDeviceKit.instance.nfc;

// 1. Listen for NFC tags
nfc.eventStream.listen((event) {
  print("NFC Tag Discovered: $event");
});

// 2. Start Reading
await nfc.readTag();

// 3. Write to a Tag
await nfc.writeTag("Hello from Flutter!");

// 4. Stop Reading
await nfc.stopReading();

3. USB Module #

import 'package:native_device_kit/native_device_kit.dart';

final usb = NativeDeviceKit.instance.usb;

// 1. Get Connected Devices
List<Map<String, dynamic>> devices = await usb.getConnectedDevices();
for (var device in devices) {
  print("Found USB Device: ${device['deviceName']} (ID: ${device['deviceId']})");
}

// 2. Open Device Connection
await usb.openDevice("DEVICE_ID");

4. Hardware Bridge (Advanced) #

Use the bridge to invoke native methods that aren't covered by the standard modules. This is useful for integrating 3rd party SDKs without modifying the plugin core.

final bridge = NativeDeviceKit.instance.bridge;

// Invoke a custom native method
try {
  final result = await bridge.invoke("customNativeMethod", {"param": "value"});
  print("Native Result: $result");
} catch (e) {
  print("Bridge Error: $e");
}

Architecture #

This plugin follows a clean, layered architecture:

1. Dart API Layer: Strong-typed, easy-to-use classes (BluetoothModule, NfcModule, etc.) that abstract the underlying platform channels.
2. Platform Channel Layer: Uses MethodChannel for command invocation and EventChannel for streaming events from native to Dart.
3. Native Implementation Layer:
   • Android: Kotlin with Coroutines and standard Android APIs (BluetoothAdapter, NfcAdapter, UsbManager).
   • iOS: Swift with CoreBluetooth, CoreNFC, and ExternalAccessory.

License #

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