android - l395 - como imprimir desde mi celular con cable usb

Cómo detectar e imprimir desde la impresora USB desde Android

Question

Estoy creando una aplicación para Android (nivel mínimo de API 16) que podría imprimir un documento desde mi dispositivo Android, donde la impresora está conectada a través de USB. Encontré un código para detectar USB desde este enlace. Adjunté mi impresora (HP Laserjet P1007) a través de USB. Pero no puede detectar la impresora.

Editado

Avancé un poco en la detección de impresoras. Soy capaz de detectar la impresora. Pero aún no puedo imprimir a través de la transferencia masiva. También intenté la transferencia asincrónica con el método usbRequest.queue

Y aquí está mi código

public class MainActivity extends Activity {
private final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
PendingIntent mPermissionIntent;
UsbManager usbManager;
UsbDevice device;
UsbDevice printer = null;
private static final int PRINTER_VENDOR_ID = 1008;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try {
setContentView(R.layout.activity_main);
Log.i("Info", "Activity started");
usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
if (deviceList.size() <= 0) {
Log.i("Info", "No device found");
} else {
Log.i("Info", "Number of device : " + deviceList.size());
((TextView) findViewById(R.id.deviceCount))
.setText("No of device : " + deviceList.size());
}
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
int count = 0;
mPermissionIntent = PendingIntent.getBroadcast(getBaseContext(), 0,
new Intent(ACTION_USB_PERMISSION), 0);
while (deviceIterator.hasNext()) {
count++;
device = deviceIterator.next();
Log.i("info", "Device No " + count + "........");
Log.i("info", "Vendor id : " + device.getVendorId());
Log.i("info", "Product id : " + device.getProductId());
Log.i("info", "Device name : " + device.getDeviceName());
Log.i("info", "Device class : " + device.getClass().getName());
Log.i("info", "Device protocol: " + device.getDeviceProtocol());
Log.i("info", "Device subclass : " + device.getDeviceSubclass());
if (device.getVendorId() == PRINTER_VENDOR_ID) {
printer = device;
break;
}
}
findViewById(R.id.buttonPrint).setOnClickListener(
new OnClickListener() {
@Override
public void onClick(View v) {
Log.i("Info", "Print command given");
IntentFilter filter = new IntentFilter(
ACTION_USB_PERMISSION);
registerReceiver(mUsbReceiver, filter);
if (printer != null) {
usbManager.requestPermission(printer,
mPermissionIntent);
} else {
Log.e("Exception", "Printer not found");
}
}
});
} catch (Exception e) {
Log.e("Exception", "Exception in onCreate " + e.getMessage());
e.printStackTrace();
}
}
private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
try {
String action = intent.getAction();
if (ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
final UsbDevice printerDevice = (UsbDevice) intent
.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (intent.getBooleanExtra(
UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
if (printerDevice != null) {
Log.i("Info", "Device permission granted");
startPrinting(printerDevice);
}
} else {
Log.d("Debug", "permission denied for device "
+ printerDevice);
}
}
}
} catch (Exception e) {
Log.e("Exception", "Exception in onRecieve " + e.getMessage());
e.printStackTrace();
}
}
};
public void startPrinting(final UsbDevice printerDevice) {
new Handler().post(new Runnable() {
UsbDeviceConnection conn;
UsbInterface usbInterface;
@Override
public void run() {
try {
Log.i("Info", "Bulk transfer started");
usbInterface = printerDevice.getInterface(0);
UsbEndpoint endPoint = usbInterface.getEndpoint(0);
conn = usbManager.openDevice(printer);
conn.claimInterface(usbInterface, true);
String myStringData = "/nThis /nis /nmy /nsample /ntext";
byte[] array = myStringData.getBytes();
ByteBuffer output_buffer = ByteBuffer
.allocate(array.length);
UsbRequest request = new UsbRequest();
request.initialize(conn, endPoint);
request.queue(output_buffer, array.length);
if (conn.requestWait() == request) {
Log.i("Info", output_buffer.getChar(0) + "");
Message m = new Message();
m.obj = output_buffer.array();
// handler.sendMessage(m);
output_buffer.clear();
} else {
Log.i("Info", "No request recieved");
}
// int transfered = conn.bulkTransfer(endPoint,
// myStringData.getBytes(),
// myStringData.getBytes().length, 5000);
// Log.i("Info", "Amount of data transferred : " +
// transfered);
} catch (Exception e) {
Log.e("Exception", "Unable to transfer bulk data");
e.printStackTrace();
} finally {
try {
conn.releaseInterface(usbInterface);
Log.i("Info", "Interface released");
conn.close();
Log.i("Info", "Usb connection closed");
unregisterReceiver(mUsbReceiver);
Log.i("Info", "Brodcast reciever unregistered");
} catch (Exception e) {
Log.e("Exception",
"Unable to release resources because : "
+ e.getMessage());
e.printStackTrace();
}
}
}
});
}
}

Y aquí está el registro que estoy recibiendo

05-29 11:59:04.627: I/Info(5369): Print command given
05-29 11:59:04.657: I/Info(5369): Device permission granted
05-29 11:59:04.657: I/Info(5369): Bulk transfer started
05-29 11:59:04.657: D/UsbRequestJNI(5369): init
05-29 11:59:04.657: I/Info(5369): ??
05-29 11:59:04.657: I/Info(5369): Interface released
05-29 11:59:04.657: D/UsbDeviceConnectionJNI(5369): close
05-29 11:59:04.657: I/Info(5369): Usb connection closed
05-29 11:59:04.657: I/Info(5369): Brodcast reciever unregistered

Pero en el lado de la impresora no recibo ninguna respuesta ...

Gracias de antemano por la ayuda.

Answer 1

Cualquiera de usar:

Intent i = new Intent(Intent.ACTION_VIEW);
i.setPackage("com.dynamixsoftware.printershare.amazon");
Uri myUri = Uri.parse(new File("file:///mnt/sdcard/download/ww.pdf").toString());
i.setDataAndType(myUri, "application/pdf");
startActivity(i);

O https://github.com/pradeepksingh/Android-USB-printer

EDITAR: Consulte https://github.com/pradeepksingh/Android-USB-printer/blob/master/com/pradeep/adapter/USBAdapter.java#L72 para obtener un buen ejemplo.

Answer 2

en lugar de usbInterface = printerDevice.getInterface(0);

recorra las interfaces disponibles y use la interfaz UsbConstants.USB_CLASS_PRINTER :

for(int i = 0; i < device.getInterfaceCount(); i++){
_interface = device.getInterface(i);
if(_interface.getInterfaceClass() == UsbConstants.USB_CLASS_PRINTER){
printer = device;
}
}

¡Lo importante es que tienes que usar una impresora basada en PDL y ninguna impresora basada en host!