Блог

Создание приложения, которое должно подключаться к устройству Bluetooth и отправлять/получать информацию. Я использую поток для подключения к разъему Bluetooth и обработчик. Приложение работает бесперебойно, но всякий раз, когда я выбираю устройство, код возвращает исключение подключения. Я перепробовал несколько устройств и проверил, подходит ли UUID. Не могу найти решение в течение нескольких дней, был бы очень признателен за помощь.

Код:

 public class MainActivity extends AppCompatActivity {  private BluetoothAdapter mybtadapter;  private Button btOn;  private Button scanBT;  static final int STATE_LISTENING=1;  static final int STATE_CONNECTING=2;  static final int STATE_CONNECTED=3;  static final int STATE_CONNECTION_FAILED=4;  static final int STATE_MESSAGE_RECEIVED=5;   int REQUEST_ENABLE_BLUETOOTH=1;   UUID MY_UUID = UUID.fromString("0F3BDD5C-0799-11E7-979A-C85B76F5CA58");  UUID myuuid;  BroadcastReceiver mReceiver;  BluetoothSocket bsock;  BluetoothConnectActivityReceiver mBluetoothPickerReceiver = new BluetoothConnectActivityReceiver();  @RequiresApi(api = Build.VERSION_CODES.O)   @Override  protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);   //Toast.makeText(MainActivity.this, "Successful Launch ", Toast.LENGTH_SHORT).show();  btOn = (Button) findViewById(R.id.BtOn);  scanBT = (Button) findViewById(R.id.scanBT);  mybtadapter = BluetoothAdapter.getDefaultAdapter();   // BLUETOOTH DEVICE PICKER  BluetoothConnectActivityReceiver mBluetoothPickerReceiver = new BluetoothConnectActivityReceiver();  registerReceiver(mBluetoothPickerReceiver, new IntentFilter(BluetoothDevicePicker.ACTION_DEVICE_SELECTED));  scanBT.setOnClickListener(v -gt; {  startActivity(new Intent(BluetoothDevicePicker.ACTION_LAUNCH)  .putExtra(BluetoothDevicePicker.EXTRA_NEED_AUTH, false)  .putExtra(BluetoothDevicePicker.EXTRA_FILTER_TYPE, BluetoothDevicePicker.FILTER_TYPE_ALL)  .setFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS));  //Toast.makeText(getApplicationContext(), "scanning.", Toast.LENGTH_SHORT).show();   });   setupBT();  BTonOff();  }   public class BluetoothConnectActivityReceiver extends BroadcastReceiver {    @Override  public void onReceive(Context context, Intent intent) {  if(BluetoothDevicePicker.ACTION_DEVICE_SELECTED.equals(intent.getAction())) {  context.unregisterReceiver(this);  BluetoothDevice device = (BluetoothDevice) intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);  Toast.makeText(context, "device : "   device.getName(), Toast.LENGTH_SHORT).show();  ClientClass clientClass=new ClientClass(device);  clientClass.start();   }  }  }   private void setupBT() {  if (mybtadapter == null) {  Toast.makeText(getApplicationContext(), "Bluetooth not supported", Toast.LENGTH_SHORT).show();  }  if (mybtadapter.isEnabled()) {  btOn.setText("Disable Bluetooth");  scanBT.setEnabled(true);   } else {  btOn.setText("Enable Bluetooth");  scanBT.setEnabled(false);  }  }   private void BTonOff() {  btOn.setOnClickListener(v -gt; {  if (mybtadapter.isEnabled()) {  mybtadapter.disable();  Toast.makeText(getApplicationContext(), "Bluetooth disabled.", Toast.LENGTH_SHORT).show();  btOn.setText("Enable Bluetooth");  scanBT.setEnabled(false);  } else {  mybtadapter.enable();  Toast.makeText(getApplicationContext(), "Bluetooth enabled.", Toast.LENGTH_SHORT).show();  btOn.setText("Disable Bluetooth");  scanBT.setEnabled(true);   }  });  }   Handler handler= new Handler(new Handler.Callback() {  @Override  public boolean handleMessage(@NonNull Message msg) {  switch (msg.what){  case STATE_LISTENING:  Toast.makeText(getApplicationContext(), "Listening", Toast.LENGTH_SHORT).show();  break;  case STATE_CONNECTING:  Toast.makeText(getApplicationContext(), "CONNECTING", Toast.LENGTH_SHORT).show();  break;  case STATE_CONNECTED:  Toast.makeText(getApplicationContext(), "CONNECTED", Toast.LENGTH_SHORT).show();  break;  case STATE_CONNECTION_FAILED:  Toast.makeText(getApplicationContext(), "CONNECTION FAILED", Toast.LENGTH_SHORT).show();  break;  case STATE_MESSAGE_RECEIVED:  //Later  break;  }  return false;  }  });   @Override  public void onDestroy() {  super.onDestroy();  if (mybtadapter.isDiscovering()){  mybtadapter.cancelDiscovery();  }  unregisterReceiver(mReceiver);   }   private class ClientClass extends Thread {  private BluetoothDevice device;  private BluetoothSocket socket;  public ClientClass (BluetoothDevice device1){  device=device1;  try {  socket= device.createInsecureRfcommSocketToServiceRecord(MY_UUID);  Log.i("ben","Successfully created socket "  socket.getRemoteDevice().getName());  } catch (IOException e) {  Log.e("ben", "Could not create socket");  e.printStackTrace();  }  }  public void run(){  try {  socket.connect();  Message message= Message.obtain();  message.what=STATE_CONNECTED;  handler.sendMessage(message);  }  catch (IOException connectException) {  Log.e("ben", "Could not connect",connectException);  Message message= Message.obtain();  message.what=STATE_CONNECTION_FAILED;  handler.sendMessage(message);  // Unable to connect; close the socket and return.  try {  socket.close();  } catch (IOException closeException) {  Log.e("ben", "Could not close the client socket", closeException);   }  return;  }    }  } }  

а вот и Логкот:

 2021-11-09 13:32:49.857 22717-11546/com.example.jhonnysnewremote E/ben: Could not connect  java.io.IOException: read failed, socket might closed or timeout, read ret: -1  at android.bluetooth.BluetoothSocket.readAll(BluetoothSocket.java:970)  at android.bluetooth.BluetoothSocket.readInt(BluetoothSocket.java:984)  at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:536)  at com.example.jhonnysnewremote.MainActivity$ClientClass.run(MainActivity.java:168)