USB Device Detection and Filtering in Android

2 min readSep 6, 2020

Hi 👋 fellow developers .

This articles discusses code for following things :

Detecting usb plug-in , plug out in Android
Filtering the devices using VendorId ProductId Class SubClass Protocol

Permission required

<uses-feature android:name="android.hardware.usb.host" />
<uses-permission android:name="android.permission.USB_PERMISSION" />

Receiver

Make it as a class for manifest declared receiver

class USBReceiver : BroadcastReceiver(){
    val TAG = "UsbReceiver"
    @SuppressLint("LogNotTimber")
    override fun onReceive(context: Context?, intent: Intent?) {
        Log.e(TAG, "Intent received" )
        if (UsbManager.ACTION_USB_DEVICE_DETACHED == intent?.action) {
            val device: UsbDevice? = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE)
            if (device?.vendorId == CAMERA_VID && device.productId == CAMERA_PID){
                Log.d(TAG, "USB Detached" )
            }
        } else if (UsbManager.ACTION_USB_DEVICE_ATTACHED == intent?.action){
            val device: UsbDevice? = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE)
            if (device?.vendorId == CAMERA_VID && device.productId == CAMERA_PID){
                Log.d(TAG, "USB Attached" )

            }
        }
    }
}

2. Object instance for context based receiver

val usbReceiver = object : BroadcastReceiver(){
    val TAG = "UsbReceiver"
    @SuppressLint("LogNotTimber")
    override fun onReceive(context: Context?, intent: Intent?) {
        Log.e(TAG, "Intent received" )
        if (UsbManager.ACTION_USB_DEVICE_DETACHED == intent?.action) {
            val device: UsbDevice? = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE)
            if (device?.vendorId == CAMERA_VID && device.productId == CAMERA_PID){
                Log.d(TAG, "USB Detached" )
            }
        } else if (UsbManager.ACTION_USB_DEVICE_ATTACHED == intent?.action){
            val device: UsbDevice? = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE)
            if (device?.vendorId == CAMERA_VID && device.productId == CAMERA_PID){
                Log.d(TAG, "USB Attached" )

            }
        }
    }
}

Device Filters for usb

Create device_filters.xml inside xml folder in res .

<resources>
    <usb-device vendor-id="12345" product-id="12345" class="123" subclass="1" protocol="1"/>    <usb-device vendor-id="12345" product-id="12345" class="123" subclass="1" protocol="1" />
</resources>

Refer link for finding out the class,subclass,protocol for your usb device .
https://www.usb.org/defined-class-codes

There are multiple ways to get the attach/detach event inside the application :

1. Manifest-declared receivers

<receiver
    android:name=".UsbReceiver"
    android:enabled="true"
    android:exported="true">
    <intent-filter>
        <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
    </intent-filter>
    <intent-filter>
        <action android:name="android.hardware.usb.action.USB_DEVICE_DETACHED" />
    </intent-filter>
    <meta-data
        android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
        android:resource="@xml/device_filter" />

2. Intent filter for activity

<activity android:name=".USBActivity">
    <intent-filter>
        <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
    </intent-filter>
<intent-filter>
        <action android:name="android.hardware.usb.action.USB_DEVICE_DETACHED" />
    </intent-filter>
    <meta-data android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
        android:resource="@xml/device_filter" />
</activity>

3. Context-registered receivers

registerReceiver(usbReceiver, IntentFilter(UsbManager.ACTION_USB_DEVICE_DETACHED,UsbManager.ACTION_USB_DEVICE_ATTACHED))

2. Unregister inside onDestroy/onStop depending on where you were registering

unregisterReceiver(usbReceiver)

Other important Links :
1. https://developer.android.com/guide/topics/connectivity/usb/host
2. https://developer.android.com/guide/components/broadcasts