<uses-permission android:name="android.permission.BLUETOOTH" />
 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />

BluetoothClass.Device.Major.PERIPHERAL

Set<BluetoothDevice> blueDevices = mBluetoothAdapter.getBondedDevices();

if (blueDevices == null || blueDevices.size() <= 0) {
 return false;
}

for (Iterator<BluetoothDevice> iterator = blueDevices.iterator(); iterator.hasNext(); ) {
 BluetoothDevice bluetoothDevice = iterator.next();

 if (bluetoothDevice.getBluetoothClass().getMajorDeviceClass() == BluetoothClass.Device.Major.PERIPHERAL) {
 //TODO 获取扫码枪设备信息
 }

}

mBluetoothAdapter.getBondedDevices()

public List getConnectedDevices (int profile) 
public int getConnectionState (BluetoothDevice device, int profile)

private void hasScanGun() {
 Configuration cfg = getResources().getConfiguration();
 return cfg.keyboard != Configuration.KEYBOARD_NOKEYS;
}

/**
 * 扫码枪事件解析类
 */
public class ScanGunKeyEventHelper {

 //延迟500ms，判断扫码是否完成。
 private final static long MESSAGE_DELAY = 500;
 //扫码内容
 private StringBuffer mStringBufferResult = new StringBuffer();
 //大小写区分
 private boolean mCaps;
 private OnScanSuccessListener mOnScanSuccessListener;
 private Handler mHandler = new Handler();

 private final Runnable mScanningFishedRunnable = new Runnable() {
 @Override
 public void run() {
  performScanSuccess();
 }
 };

 //返回扫描结果
 private void performScanSuccess() {
 String barcode = mStringBufferResult.toString();
 if (mOnScanSuccessListener != null)
  mOnScanSuccessListener.onScanSuccess(barcode);
 mStringBufferResult.setLength(0);
 }

 //key事件处理
 public void analysisKeyEvent(KeyEvent event) {

 int keyCode = event.getKeyCode();

 //字母大小写判断
 checkLetterStatus(event);

 if (event.getAction() == KeyEvent.ACTION_DOWN) {

  char aChar = getInputCode(event);;

  if (aChar != 0) {
  mStringBufferResult.append(aChar);
  }

  if (keyCode == KeyEvent.KEYCODE_ENTER) {
  //若为回车键，直接返回
  mHandler.removeCallbacks(mScanningFishedRunnable);
  mHandler.post(mScanningFishedRunnable);
  } else {
  //延迟post，若500ms内，有其他事件
  mHandler.removeCallbacks(mScanningFishedRunnable);
  mHandler.postDelayed(mScanningFishedRunnable, MESSAGE_DELAY);
  }

 }
 }

 //检查shift键
 private void checkLetterStatus(KeyEvent event) {
 int keyCode = event.getKeyCode();
 if (keyCode == KeyEvent.KEYCODE_SHIFT_RIGHT || keyCode == KeyEvent.KEYCODE_SHIFT_LEFT) {
  if (event.getAction() == KeyEvent.ACTION_DOWN) {
  //按着shift键，表示大写
  mCaps = true;
  } else {
  //松开shift键，表示小写
  mCaps = false;
  }
 }
 }


 //获取扫描内容
 private char getInputCode(KeyEvent event) {

 int keyCode = event.getKeyCode();

 char aChar;

 if (keyCode >= KeyEvent.KEYCODE_A && keyCode <= KeyEvent.KEYCODE_Z) {
  //字母
  aChar = (char) ((mCaps ? 'A' : 'a') + keyCode - KeyEvent.KEYCODE_A);
 } else if (keyCode >= KeyEvent.KEYCODE_0 && keyCode <= KeyEvent.KEYCODE_9) {
  //数字
  aChar = (char) ('0' + keyCode - KeyEvent.KEYCODE_0);
 } else {
  //其他符号
  switch (keyCode) {
  case KeyEvent.KEYCODE_PERIOD:
   aChar = '.';
   break;
  case KeyEvent.KEYCODE_MINUS:
   aChar = mCaps ? '_' : '-';
   break;
  case KeyEvent.KEYCODE_SLASH:
   aChar = '/';
   break;
  case KeyEvent.KEYCODE_BACKSLASH:
   aChar = mCaps ? '|' : '\\';
   break;
  default:
   aChar = 0;
   break;
  }
 }

 return aChar;

 }




 public interface OnScanSuccessListener {
 public void onScanSuccess(String barcode);
 }

 public void setOnBarCodeCatchListener(OnScanSuccessListener onScanSuccessListener) {
 mOnScanSuccessListener = onScanSuccessListener;
 }

 public void onDestroy() {
 mHandler.removeCallbacks(mScanningFishedRunnable);
 mOnScanSuccessListener = null;
 }

}

 /**
 * Activity截获按键事件.发给ScanGunKeyEventHelper
 *
 * @param event
 * @return
 */
 @Override
 public boolean dispatchKeyEvent(KeyEvent event) {

 if (isScanGunEvent(event)) {
  mScanGunKeyEventHelper.analysisKeyEvent(event);
  return true;
 }
 return super.dispatchKeyEvent(event);
 }

 /**
 * 显示扫描内容
 * @param barcode 条形码
 */
 @Override
 public void onScanSuccess(String barcode) {
 //TODO 显示扫描内容
 }

private void hasScanGun() {
 Configuration cfg = getResources().getConfiguration();
 return cfg.keyboard != Configuration.KEYBOARD_NOKEYS;
}

/**
 * 判断是否已经连接扫码枪
 * @return
 */
protected boolean hasScanGun() {

 Set<BluetoothDevice> blueDevices = mBluetoothAdapter.getBondedDevices();

 if (blueDevices == null || blueDevices.size() <= 0) {
 return false;
 }

 for (Iterator<BluetoothDevice> iterator = blueDevices.iterator(); iterator.hasNext(); ) {
 BluetoothDevice bluetoothDevice = iterator.next();

 if (bluetoothDevice.getBluetoothClass().getMajorDeviceClass() == BluetoothClass.Device.Major.PERIPHERAL) {
  return isInputDeviceUsed(bluetoothDevice.getName());
 }

 }

 return false;

}



private boolean isInputDeviceUsed(String deviceName) {

 int[] deviceIds = InputDevice.getDeviceIds();

 for (int id : deviceIds) {
 if (InputDevice.getDevice(id).getName().equals(deviceName)) {
  return true;
 }
 }

 return false;

}

key 11 0
key 2 1
key 3 2
key 4 3
key 5 4
key 6 5
key 7 6
key 8 7
key 9 8
key 10 9
key 12 MINUS
key 13 EQUALS
key 14 DEL
key 15 TAB