嘿，我是Android开发的新手，并在android中获得了一些初学者知识 现在我正在做一个通过usb与热敏打印机连接的应用程序，实际上我打印的文件文件中有一些参考堆栈溢出但我需要打印关于输入的条形码。我正在尝试打印1D条码但我是不成功。任何人都会为我的问题提出一些建议或解决方案。
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mUsbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
mDeviceList = mUsbManager.getDeviceList();
mDeviceIterator = mDeviceList.values().iterator();
Button print = (Button) findViewById(R.id.print);
final Button printBarcode = findViewById(R.id.barcode);
Toast.makeText(this, "Device List Size: " + String.valueOf(mDeviceList.size()), Toast.LENGTH_SHORT).show();
TextView textView = (TextView) findViewById(R.id.usbDevice);
String usbDevice = "";
//This is just testing what devices are connected
while (mDeviceIterator.hasNext()) {
UsbDevice usbDevice1 = mDeviceIterator.next();
usbDevice += "\n" +
"DeviceID: " + usbDevice1.getDeviceId() + "\n" +
"DeviceName: " + usbDevice1.getDeviceName() + "\n" +
"DeviceClass: " + usbDevice1.getDeviceClass() + " - " + translateDeviceClass(usbDevice1.getDeviceClass()) + "\n" +
"DeviceSubClass: " + usbDevice1.getDeviceSubclass() + "\n" +
"VendorID: " + usbDevice1.getVendorId() + "\n" +
"ProductID: " + usbDevice1.getProductId() + "\n";
int interfaceCount = usbDevice1.getInterfaceCount();
Toast.makeText(this, "INTERFACE COUNT: " + String.valueOf(interfaceCount), Toast.LENGTH_SHORT).show();
mDevice = usbDevice1;
if (mDevice == null) {
Toast.makeText(this, "mDevice is null", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, "mDevice is not null", Toast.LENGTH_SHORT).show();
}
textView.setText(usbDevice);
}
if (mDevice == null) {
Toast.makeText(this, "mDevice is null", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, "mDevice is not null", Toast.LENGTH_SHORT).show();
}
mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
registerReceiver(mUsbReceiver, filter);
mUsbManager.requestPermission(mDevice, mPermissionIntent);
print.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
print(mConnection, mInterface);
}
});
printBarcode.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
printBarcode(mConnection,mInterface);
}
});
}
private String translateDeviceClass(int deviceClass) {
switch (deviceClass) {
case UsbConstants.USB_CLASS_APP_SPEC:
return "Application specific USB class";
case UsbConstants.USB_CLASS_AUDIO:
return "USB class for audio devices";
case UsbConstants.USB_CLASS_CDC_DATA:
return "USB class for CDC devices (communications device class)";
case UsbConstants.USB_CLASS_COMM:
return "USB class for communication devices";
case UsbConstants.USB_CLASS_CONTENT_SEC:
return "USB class for content security devices";
case UsbConstants.USB_CLASS_CSCID:
return "USB class for content smart card devices";
case UsbConstants.USB_CLASS_HID:
return "USB class for human interface devices (for example, mice and keyboards)";
case UsbConstants.USB_CLASS_HUB:
return "USB class for USB hubs";
case UsbConstants.USB_CLASS_MASS_STORAGE:
return "USB class for mass storage devices";
case UsbConstants.USB_CLASS_MISC:
return "USB class for wireless miscellaneous devices";
case UsbConstants.USB_CLASS_PER_INTERFACE:
return "USB class indicating that the class is determined on a per-interface basis";
case UsbConstants.USB_CLASS_PHYSICA:
return "USB class for physical devices";
case UsbConstants.USB_CLASS_PRINTER:
return "USB class for printers";
case UsbConstants.USB_CLASS_STILL_IMAGE:
return "USB class for still image devices (digital cameras)";
case UsbConstants.USB_CLASS_VENDOR_SPEC:
return "Vendor specific USB class";
case UsbConstants.USB_CLASS_VIDEO:
return "USB class for video devices";
case UsbConstants.USB_CLASS_WIRELESS_CONTROLLER:
return "USB class for wireless controller devices";
default:
return "Unknown USB class!";
}
}
Broadcast receiver to obtain permission from user for connection
final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
UsbDevice device = (UsbDevice)
intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED,
false)) {
if (device != null) {
//call method to set up device communication
mInterface = device.getInterface(0);
mEndPoint = mInterface.getEndpoint(0);
mConnection = mUsbManager.openDevice(device);
//setup();
}
} else {
//Log.d("SUB", "permission denied for device " + device);
Toast.makeText(context, "PERMISSION DENIED FOR THIS DEVICE", Toast.LENGTH_SHORT).show();
}
}
}
}
};
打印文本文件
private void print(UsbDeviceConnection connection, UsbInterface intrface) {
String test = "Together Forever";
byte[] testBytes = test.getBytes(Charset.forName("UTF-8"));
if (intrface == null) {
Toast.makeText(this, "INTERFACE IS NULL", Toast.LENGTH_SHORT).show();
}
if (connection == null) {
Toast.makeText(this, "CONNECTION IS NULL", Toast.LENGTH_SHORT).show();
}
if (forceCLaim == null) {
Toast.makeText(this, "FORCE CLAIM IS NULL", Toast.LENGTH_SHORT).show();
}
connection.claimInterface(intrface, forceCLaim);
connection.bulkTransfer(mEndPoint, testBytes, testBytes.length, 0);
打印条形码
private void printBarcode(UsbDeviceConnection connection, UsbInterface intrface){
String content = "115";
//1D barcode format (hex): 1d 6b 02 0d + barcode data
byte[] formats = {(byte) 0x1d, (byte) 0x6b, (byte) 0x02, (byte) 0x0d};
byte[] contents = content.getBytes();
byte[] bytes = new byte[formats.length + contents.length];
System.arraycopy(formats, 0, bytes, 0, formats.length);
System.arraycopy(contents, 0, bytes, formats.length, contents.length);
connection.claimInterface(intrface, forceCLaim);
connection.bulkTransfer(mEndPoint, bytes, bytes.length, 0);
在谷歌搜索大量解决方案，但我没有得到任何正确的解决方案。
答案 0 :(得分：0)
我已经实现了这个并且工作但可能使用了您使用的不同打印机
检查此答案以获取参考https://stackoverflow.com/a/35243569/4168314
此处修改后的代码与您的代码匹配：
private void printBarcode(UsbDeviceConnection connection, UsbInterface intrface) {
String content = "115";
byte[] contents = content.getBytes();
byte[] formats = {(byte) 0x1d, (byte) 0x6b, (byte) 0x49, (byte)contents.length};
byte[] bytes = new byte[formats.length + contents.length];
System.arraycopy(formats, 0, bytes, 0, formats.length );
System.arraycopy(contents, 0, bytes, formats.length, contents.length);
connection.claimInterface(intrface, forceCLaim);
connection.bulkTransfer(mEndPoint, bytes, bytes.length, 0);
}