Putting an android device in USB Host Mode?

Question

For my application I need to make the android device act as the USB Host. It needs to send and receive data from USB connected devices. I have gone through USB Host in Android Developers Site, and developed sample code as follows:

Main.java

public class UsbDemoProjActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Button btn = (Button)findViewById(R.id.button1);
        btn.setOnClickListener( new OnClickListener() {
        @Override
        public void onClick(View v) {
            Toast.makeText(getApplicationContext(), "button click", 30).show();

                Intent it = new Intent(UsbDemoProjActivity.this,Second.class);
                startActivity(it);
            }
        });
    }
}

Second.java:

public class Second extends Activity{
    UsbDevice device;
    UsbManager mUsbManager;
    PendingIntent mPermissionIntent;
    private static String ACTION_USB_PERMISSION ="com.android.example.USB_PERMISSION";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        System.out.println("111111111");
        mUsbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
        ACTION_USB_PERMISSION ="com.android.example.USB_PERMISSION";
        System.out.println("2222222222");
        HashMap<String, UsbDevice> deviceList = mUsbManager.getDeviceList();
        device = deviceList.get("deviceName");
        System.out.println("33333333333");
        mPermissionIntent = PendingIntent.getBroadcast(this, 0, 
                                            new Intent(ACTION_USB_PERMISSION), 0);
        System.out.println("444444444444");
        IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
        System.out.println("555555555555");
        registerReceiver(mUsbReceiver, filter);
        System.out.println("66666666666");
        mUsbManager.requestPermission(device, mPermissionIntent);
    }

    private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            System.out.println("7777777777777");
            if (ACTION_USB_PERMISSION.equals(action)) {
                synchronized (this) {
                    System.out.println("88888888888");
                    UsbDevice device = (UsbDevice)intent.getParcelableExtra( 
                                                      UsbManager.EXTRA_DEVICE);

                    if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
                        if(device != null){
                            System.out.println("99999999999999");
                            //call method to set up device communication
                        }
                    } else {
                        //Log.d(TAG, "permission denied for device " + device);
                        System.out.println("permission denied for device" + device);
                    }
                }
            }
        }
    };
}

However, when I click on button in Main.java page it is showing an error as:

Unfortunately USBDemoProj has been stopped

and in logcat displaying error as per the below image but here the system.output() lines are displaying which are declared in Second.java class. Can anyone please help me what is the error in my app?

Also, am I using the correct method in my sample code to access devices in USB Host Mode? Can anyone suggest me a better way?

Answer 1

I'm using a slickdev library to talk to my serial device, so I'm not sure about your code. It's not onDataReceived()? That might just be the library's function but...

our manifests should both have this in it:

    <uses-feature android:name="android.hardware.usb.host" android:required="true"></uses-feature>

and in the

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