android打印机没反应了,使用蓝牙打印机在Android中打印不起作用

我正在研究的应用程序允许用户创建PDF，并且还允许使用蓝牙打印机打印它。

我创建了PDF，但每当我打算使用蓝牙打印机集成打印功能时，它就会在那里发生错误。

我无法获取蓝牙设备列表。

如果您有任何示例代码，请将其提供给我。这对我来说太重要了。

这是我的代码

PrintActivity.java

public class PrintActivity extends Activity implements Runnable {

int idd;

protected static final String TAG = “TAG”;

private static final int REQUEST_CONNECT_DEVICE = 1;

private static final int REQUEST_ENABLE_BT = 2;

Button btnPrinr;

BluetoothAdapter mBluetoothAdapter;

private UUID applicationUUID = UUID.fromString(“00001101-0000-1000-8000-00805F9B34FB”);

private ProgressDialog mBluetoothConnectProgressDialog;

private BluetoothSocket mBluetoothSocket;

BluetoothDevice mBluetoothDevice;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_print);

idd = getIntent().getIntExtra(“ID”, 0);

Log.e(“ID”, “” + idd);

btnPrinr = (Button) findViewById(R.id.btnPrinr);

btnPrinr.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

if (mBluetoothAdapter == null) {

Toast.makeText(PrintActivity.this, “Message1”, Toast.LENGTH_SHORT).show();

} else {

if (!mBluetoothAdapter.isEnabled()) {

Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);

startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

} else {

ListPairedDevices();

Intent connectIntent = new Intent(PrintActivity.this, DeviceListActivity.class);

startActivityForResult(connectIntent, REQUEST_CONNECT_DEVICE);

}

}

}

});

}

public void onActivityResult(int mRequestCode, int mResultCode, Intent mDataIntent) {

super.onActivityResult(mRequestCode, mResultCode, mDataIntent);

switch (mRequestCode) {

case REQUEST_CONNECT_DEVICE:

if (mResultCode == Activity.RESULT_OK) {

Bundle mExtra = mDataIntent.getExtras();

String mDeviceAddress = mExtra.getString(“DeviceAddress”);

Log.v(TAG, “Coming incoming address ” + mDeviceAddress);

mBluetoothDevice = mBluetoothAdapter.getRemoteDevice(mDeviceAddress);

mBluetoothConnectProgressDialog = ProgressDialog.show(this, “Connecting…”, mBluetoothDevice.getName() + ” : ” + mBluetoothDevice.getAddress(), true, false);

Thread mBlutoothConnectThread = new Thread(this);

mBlutoothConnectThread.start();

//pairToDevice(mBluetoothDevice); This method is replaced by progress dialog with thread

}

break;

case REQUEST_ENABLE_BT:

if (mResultCode == Activity.RESULT_OK) {

ListPairedDevices();

Intent connectIntent = new Intent(PrintActivity.this, DeviceListActivity.class);

startActivityForResult(connectIntent, REQUEST_CONNECT_DEVICE);

} else {

Toast.makeText(PrintActivity.this, “Message”, Toast.LENGTH_SHORT).show();

}

break;

}

}

private void ListPairedDevices() {

Set mPairedDevices = mBluetoothAdapter.getBondedDevices();

if (mPairedDevices.size() > 0) {

for (BluetoothDevice mDevice : mPairedDevices) {

Log.v(TAG, “PairedDevices: ” + mDevice.getName() + ” ” + mDevice.getAddress());

}

}

}

public void run() {

try {

mBluetoothSocket = mBluetoothDevice.createRfcommSocketToServiceRecord(applicationUUID);

mBluetoothAdapter.cancelDiscovery();

mBluetoothSocket.connect();

mHandler.sendEmptyMessage(0);

} catch (IOException eConnectException) {

Log.d(TAG, “CouldNotConnectToSocket”, eConnectException);

closeSocket(mBluetoothSocket);

return;

}

}

private void closeSocket(BluetoothSocket nOpenSocket) {

try {

nOpenSocket.close();

Log.d(TAG, “SocketClosed”);

} catch (IOException ex) {

Log.d(TAG, “CouldNotCloseSocket”);

}

}

private Handler mHandler = new Handler() {

@Override

public void handleMessage(Message msg) {

mBluetoothConnectProgressDialog.dismiss();

Toast.makeText(PrintActivity.this, “DeviceConnected”, Toast.LENGTH_SHORT).show();

}

};

}

DeviceListActivity.java

public class DeviceListActivity extends Activity {

protected static final String TAG = “TAG”;

private BluetoothAdapter mBluetoothAdapter;

private ArrayAdapter mPairedDevicesArrayAdapter;

TextView txtName;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);

setContentView(R.layout.activity_device_list);

setResult(Activity.RESULT_CANCELED);

mPairedDevicesArrayAdapter = new ArrayAdapter(this, R.layout.simple_list_raw,R.id.txtName);

ListView mPairedListView = (ListView) findViewById(R.id.paired_devices);

mPairedListView.setAdapter(mPairedDevicesArrayAdapter);

mPairedListView.setOnItemClickListener(mDeviceClickListener);

mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

Set mPairedDevices = mBluetoothAdapter.getBondedDevices();

if (mPairedDevices.size() > 0) {

findViewById(R.id.title_paired_devices).setVisibility(View.VISIBLE);

for (BluetoothDevice mDevice : mPairedDevices) {

mPairedDevicesArrayAdapter.add(mDevice.getName() + “\n” + mDevice.getAddress());

}

} else {

String mNoDevices = getResources().getText(R.string.none_paired).toString();

mPairedDevicesArrayAdapter.add(mNoDevices);

}

}

@Override

protected void onDestroy() {

super.onDestroy();

if (mBluetoothAdapter != null) {

mBluetoothAdapter.cancelDiscovery();

}

}

private OnItemClickListener mDeviceClickListener = new OnItemClickListener() {

public void onItemClick(AdapterView> mAdapterView, View mView, int mPosition, long mLong) {

mBluetoothAdapter.cancelDiscovery();

String mDeviceInfo = ((TextView) mView).getText().toString();

String mDeviceAddress = mDeviceInfo.substring(mDeviceInfo.length() – 15);

Log.v(TAG, “Device_Address ” + mDeviceAddress);

Bundle mBundle = new Bundle();

mBundle.putString(“DeviceAddress”, mDeviceAddress);

Intent mBackIntent = new Intent();

mBackIntent.putExtras(mBundle);

setResult(Activity.RESULT_OK, mBackIntent);

finish();

}

};

}