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这次实际项目中要求了手机终端和低功耗蓝牙即蓝牙4.0通讯的功能,所以这次我也就把我自己的Android代码同大家分享,稍后考虑将框架整理后上传Github供大家交流学习。
//初始化蓝牙设备 private void init_ble() { // 手机硬件支持蓝牙 if (!getPackageManager().hasSystemFeature( PackageManager.FEATURE_BLUETOOTH_LE)) { Toast.makeText(this, "不支持BLE", Toast.LENGTH_SHORT).show(); } // Initializes Bluetooth adapter. // 获取手机本地的蓝牙适配器 final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE); mBluetoothAdapter = bluetoothManager.getAdapter(); // 打开蓝牙权限 if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) { Intent enableBtIntent = new Intent( BluetoothAdapter.ACTION_REQUEST_ENABLE); startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT); } }
首先判断手机硬件是否支持低功耗蓝牙,如果支持那么获取手机的蓝牙适配器,接着判断蓝牙权限是否已经开启,如果未开启则去申请。
在这里大家也可以重写onActivityResult方法来对蓝牙开启成功后进行一个提示,这里我就没有写了。
在这里我们单独使用一个Fragment来进行蓝牙功能的演示,界面如下:
具体布局很简单,主要就是几个扫描和断开连接,下面三个按钮与此功能无关,是发送命令的,中间的listview显示可以连接的设备。好了,下面我们将重点讲解具体的程序流程。
包括以下几个:
//扫描蓝牙按钮 private Button btnScan; //取消蓝牙连接按钮 private Button btnDiscoonect; //蓝牙适配器 BluetoothAdapter mBluetoothAdapter; // 蓝牙信号强度 private ArrayListrssis; // 自定义Adapter LeDeviceListAdapter mleDeviceListAdapter; //蓝牙连接状态 private boolean mConnected = false; private String status = "disconnected"; //蓝牙特征值 private ArrayList > mGattCharacteristics = new ArrayList >(); private static BluetoothGattCharacteristic target_chara = null; //蓝牙设备的list private ListView lvDevice; // 描述扫描蓝牙的状态 private boolean mScanning; private boolean scan_flag; //设备信息 public String deviceName; public String deviceAddress; public String deviceRssi; // 蓝牙扫描时间 private static final long SCAN_PERIOD = 10000;
case R.id.btn_scan_dev: if (scan_flag) { boolean gps_able = false; mleDeviceListAdapter = new LeDeviceListAdapter(); lvDevice.setAdapter(mleDeviceListAdapter); gps_able = isGpsEnable(getActivity()); if (gps_able == true) { scanLeDevice(true); } else { Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS); int requestCode = 1; this.startActivityForResult(intent, requestCode); } } else { scanLeDevice(false); btnScan.setText("Scan Device"); } break;
注意:大家可能会对其中对于GPS的操作感到疑惑,但是在Android6.0之后的系统中,想要扫描到蓝牙必须动态添加位置权限。
首先判断当前是否已经扫描,初始flag为true,然后初始化listview的适配器并检查当前位置权限有没有开启,如果开启了则开始扫描。
private void scanLeDevice(final boolean enable) { if (enable) { /* 开始扫描蓝牙设备,带mLeScanCallback 回调函数 */ Log.i("SCAN", "begin....................."); mScanning = true; scan_flag = false; btnScan.setText("Stop Scanning"); mBluetoothAdapter.startLeScan(mLeScanCallback); //TODO:版本 /*if(android.os.Build.VERSION.SDK_INT<21) bluetoothAdapter.startLeScan(this); else{ bluetoothLeScanner.startScan(callBack); }*/ } else { Log.i("Stop", "stoping................"); mScanning = false; mBluetoothAdapter.stopLeScan(mLeScanCallback); scan_flag = true; } }
核心还是调用了蓝牙适配器的startLeScan方法或者StartScan方法,这个看你的API版本了,下面我们需要重写我们的LeScanCallback函数,用来扫描到的蓝牙信息并添加到我们的listview中去。
/** * 蓝牙扫描回调函数 实现扫描蓝牙设备,回调蓝牙BluetoothDevice,可以获取name MAC等信息 **/ private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() { @Override public void onLeScan(final BluetoothDevice device, final int rssi, byte[] scanRecord) { // TODO Auto-generated method stub getActivity().runOnUiThread(new Runnable() { @Override public void run() { /* 讲扫描到设备的信息输出到listview的适配器 */ mleDeviceListAdapter.addDevice(device, rssi); mleDeviceListAdapter.notifyDataSetChanged(); } }); System.out.println("Address:" + device.getAddress()); System.out.println("Name:" + device.getName()); System.out.println("rssi:" + rssi); } };
注意我们是在Fragment中运行的,想要修改UI需要利用上述runOnUiThread方法。
以上就完成了扫描蓝牙设备并添加更新listview的功能了。
当点击的listview中展示的对应设备Item的时候我们将对此设备进行连接:
/* listview点击函数 */ lvDevice.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView arg0, View v, int position, long id) { // TODO Auto-generated method stub final BluetoothDevice device = mleDeviceListAdapter .getDevice(position); //这里是更新工具类的信息,可以不看 fBleUtils.setDeviceName(device.getName()); fBleUtils.setDeviceAddress(device.getAddress()); fBleUtils.setRssi(rssis.get(position).toString()); fBleUtils.setBluetoothDevice(device); fBleUtils.setBluetoothAdapter(mBluetoothAdapter); //获取Item的信息 deviceName = device.getName(); deviceAddress = device.getAddress(); deviceRssi = rssis.get(position).toString(); if (device == null) return; //扫描到蓝牙设备即为true if (mScanning) { /* 停止扫描设备 */ mBluetoothAdapter.stopLeScan(mLeScanCallback); mScanning = false; } try { //启动蓝牙服务 Intent gattServiceIntent = new Intent(getActivity(), BluetoothLeService.class); getActivity().bindService(gattServiceIntent, mServiceConnection, BIND_AUTO_CREATE); //注册广播接收器 getActivity().registerReceiver(mGattUpdateReceiver, makeGattUpdateIntentFilter()); if (mBluetoothLeService != null) { //根据蓝牙地址,建立连接 final boolean result = mBluetoothLeService.connect(deviceAddress); Log.d(TAG, "Connect request result=" + result); } } catch (Exception e) { e.printStackTrace(); // TODO: handle exception } } });
首先获取我们点击的设备Item的相关信息,然后关闭扫描。
之后我们需要启动我们的蓝牙服务类(这个类会在下面一节介绍),相当于启动了蓝牙服务。
最后我们根据定义的过滤器来为当前活动注册一个广播接收器(接收蓝牙服务类传来的信息),并根据地址来建立连接。
/* BluetoothLeService绑定的回调函数 */ private final ServiceConnection mServiceConnection = new ServiceConnection() { @Override public void onServiceConnected(ComponentName componentName, IBinder service) { mBluetoothLeService = ((BluetoothLeService.LocalBinder) service).getService(); if (!mBluetoothLeService.initialize()) { Log.e(TAG, "Unable to initialize Bluetooth"); } // Automatically connects to the device upon successful start-up // initialization. // 根据蓝牙地址,连接设备 mBluetoothLeService.connect(deviceAddress); } @Override public void onServiceDisconnected(ComponentName componentName) { } };
具体注册2.4已经说明了,这里把接收器内容提一下:
/** * 广播接收器,负责接收BluetoothLeService类发送的数据 */ private final BroadcastReceiver mGattUpdateReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { final String action = intent.getAction(); if (BluetoothLeService.ACTION_GATT_CONNECTED.equals(action))//Gatt连接成功 { mConnected = true; status = "connected"; //更新连接状态 updateConnectionState(status); System.out.println("BroadcastReceiver :" + "device connected"); Toast.makeText(getActivity(),"AM_Tool连接成功!",Toast.LENGTH_SHORT).show(); } else if (BluetoothLeService.ACTION_GATT_DISCONNECTED//Gatt连接失败 .equals(action)) { mConnected = false; status = "disconnected"; //更新连接状态 updateConnectionState(status); System.out.println("BroadcastReceiver :" + "device disconnected"); Toast.makeText(getActivity(),"AM_Tool连接失败!",Toast.LENGTH_SHORT).show(); } else if (BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED//发现GATT服务器 .equals(action)) { // Show all the supported services and characteristics on the // user interface. //获取设备的所有蓝牙服务 displayGattServices(mBluetoothLeService .getSupportedGattServices()); System.out.println("BroadcastReceiver :" + "device SERVICES_DISCOVERED"); } else if (BluetoothLeService.ACTION_DATA_AVAILABLE.equals(action))//有效数据 { //处理发送过来的数据 displayData(intent.getExtras().getString( BluetoothLeService.EXTRA_DATA)); System.out.println("BroadcastReceiver onData:" + intent.getStringExtra(BluetoothLeService.EXTRA_DATA)); } } };
/* 更新连接状态 */
private void updateConnectionState(String status) { tvStatus.setText(status); if (status.equals(“connected”)){ btnDiscoonect.setEnabled(true); }else { btnDiscoonect.setEnabled(false); } }过滤器:
/* 意图过滤器 */ private static IntentFilter makeGattUpdateIntentFilter() { final IntentFilter intentFilter = new IntentFilter(); intentFilter.addAction(BluetoothLeService.ACTION_GATT_CONNECTED); intentFilter.addAction(BluetoothLeService.ACTION_GATT_DISCONNECTED); intentFilter.addAction(BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED); intentFilter.addAction(BluetoothLeService.ACTION_DATA_AVAILABLE); return intentFilter; }
其实逻辑很简单,根据蓝牙服务类intent传来的action的类别进行不同的处理,对应的action已经通过Filter添加了。
主要就是根据蓝牙连接情况进行用户提示以及UI变更:Gatt连接成功时候提示连接成功并更新TextView,失败时候同理。
displayGattServices这个方法我也将在下面介绍一下,但是这个功能应该是固定的,如果就是使用的话不需要变动。
下面的displayData就是对于我们开发者来说比较重要的功能了,它主要获得蓝牙服务接收到的数据包,简而言之就是协议处理过后的下位机或者终端发送的数据了:
/** * @param @param rev_string(接受的数据) * @return void * @throws * @Title: displayData * @Description: TODO(接收到的数据另外两个Fragment中显示!!!) */ private void displayData(final String rev_string) { getActivity().runOnUiThread(new Runnable() { @Override public void run() { String[] direction = rev_string.split("="); if (direction[0].equals("left_distance")){ fBleUtils.setLeftXLocation(60.0f - Float.parseFloat(direction[1])); fBleUtils.setLeftDistance(Float.parseFloat(direction[1])); }else if (direction[0].equals("center_distance")){ fBleUtils.setCenterYLocation(60.0f - Float.parseFloat(direction[1])); fBleUtils.setCenterDistance(Float.parseFloat(direction[1])); }else if (direction[0].equals("right_distance")){ fBleUtils.setRightFloatDistance(Float.parseFloat(direction[1])); fBleUtils.setRightDistance(Float.parseFloat(direction[1])); } tvStatus.setText(rev_string); mDrawerActivity.setBleUtils(fBleUtils); btnDiscoonect.setEnabled(true); } }); }
这里我们用这个数据更新了我们的对应数据TextView与工具类
//TODO:选择关闭和开启的红外测距模块 case R.id.btn_left_operation: if (btnLeftOp.getText().equals("L_Open")) { Toast.makeText(getActivity(),"打开左边红外测距器",Toast.LENGTH_SHORT).show(); target_chara.setValue("3"); //调用蓝牙服务的写特征值方法实现发送数据 mBluetoothLeService.writeCharacteristic(target_chara); btnLeftOp.setText(R.string.left_close_status); } else { Toast.makeText(getActivity(),"关闭左边红外测距器",Toast.LENGTH_SHORT).show(); target_chara.setValue("2"); //调用蓝牙服务的写特征值方法实现发送数据 mBluetoothLeService.writeCharacteristic(target_chara); btnLeftOp.setText(R.string.left_open_status); } break;
这里我们以一个命令发送按钮为例,首先我们需要给特征值target_chara赋值,然后调用蓝牙服务的发送特征值的命令即可,前提是我们已经连接上了对应设备。
以上我们基本完成了蓝牙初始化-扫描发现蓝牙设备-蓝牙设备的连接-蓝牙接收信息的读取-蓝牙信息的发送这样一套基本的开发流程,如果只是使用蓝牙,那么以上的信息和步骤应该可以满足需求。下面我将具体分析蓝牙服务这个类的功能,帮助大家更好的理解蓝牙通信。
这个蓝牙服务类运行于后台,帮助我们同蓝牙设备进行连接,并和蓝牙Fragment的广播接收器进行交流,完成蓝牙数据接收和发送的功能。
private final static String TAG = "BluetoothLeService";// luetoothLeService.class.getSimpleName(); private ListmEnabledSensors = new ArrayList (); //蓝牙相关类 private BluetoothManager mBluetoothManager; private BluetoothAdapter mBluetoothAdapter; private String mBluetoothDeviceAddress; private BluetoothGatt mBluetoothGatt; private int mConnectionState = STATE_DISCONNECTED; private static final int STATE_DISCONNECTED = 0; private static final int STATE_CONNECTING = 1; private static final int STATE_CONNECTED = 2; public final static String ACTION_GATT_CONNECTED = "com.example.bluetooth.le.ACTION_GATT_CONNECTED"; public final static String ACTION_GATT_DISCONNECTED = "com.example.bluetooth.le.ACTION_GATT_DISCONNECTED"; public final static String ACTION_GATT_SERVICES_DISCOVERED = "com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED"; public final static String ACTION_DATA_AVAILABLE = "com.example.bluetooth.le.ACTION_DATA_AVAILABLE"; public final static String EXTRA_DATA = "com.example.bluetooth.le.EXTRA_DATA"; // public final static UUID UUID_HEART_RATE_MEASUREMENT =zzzzzzzzzzzzz // UUID.fromString(SampleGattAttributes.HEART_RATE_MEASUREMENT); private OnDataAvailableListener mOnDataAvailableListener;
这里比较重要的就是BluetoothGatt这个类,这个类通过同给定address的终端设备连接后获得,通过这个类去进行蓝牙通信的操作。
这个方法是BleFragment里面BluetoothLeService绑定的回调函数里面调用的:
private final ServiceConnection mServiceConnection = new ServiceConnection() { @Override public void onServiceConnected(ComponentName componentName, IBinder service) { mBluetoothLeService = ((BluetoothLeService.LocalBinder) service).getService(); if (!mBluetoothLeService.initialize()) { Log.e(TAG, "Unable to initialize Bluetooth"); } // Automatically connects to the device upon successful start-up // initialization. // 根据蓝牙地址,连接设备 mBluetoothLeService.connect(deviceAddress); } @Override public void onServiceDisconnected(ComponentName componentName) { } };
首先获取服务,然后进行服务的初始化,接着根据地址进行蓝牙设备的连接,初始化代码如下:
/* service 中蓝牙初始化 */ public boolean initialize() { // For API level 18 and above, get a reference to BluetoothAdapter // through // BluetoothManager. if (mBluetoothManager == null) { //获取系统的蓝牙管理器 mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE); if (mBluetoothManager == null) { Log.e(TAG, "Unable to initialize BluetoothManager."); return false; } } mBluetoothAdapter = mBluetoothManager.getAdapter(); if (mBluetoothAdapter == null) { Log.e(TAG, "Unable to obtain a BluetoothAdapter."); return false; } return true; }
这里的初始化就是获取当前系统的蓝牙适配器
上一节当中我们直接在Fragment里面使用了服务类的connect方法进行连接,这里我们分析里面的功能:
// 连接远程蓝牙 public boolean connect(final String address) { if (mBluetoothAdapter == null || address == null) { Log.w(TAG, "BluetoothAdapter not initialized or unspecified address."); return false; } // Previously connected device. Try to reconnect. if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress) && mBluetoothGatt != null) { Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection."); if (mBluetoothGatt.connect())//连接蓝牙,其实就是调用BluetoothGatt的连接方法 { mConnectionState = STATE_CONNECTING; return true; } else { return false; } } /* 获取远端的蓝牙设备 */ final BluetoothDevice device = mBluetoothAdapter .getRemoteDevice(address); if (device == null) { Log.w(TAG, "Device not found. Unable to connect."); return false; } // We want to directly connect to the device, so we are setting the // autoConnect // parameter to false. /* 调用device中的connectGatt连接到远程设备 */ mBluetoothGatt = device.connectGatt(this, false, mGattCallback); Log.d(TAG, "Trying to create a new connection."); mBluetoothDeviceAddress = address; mConnectionState = STATE_CONNECTING; System.out.println("device.getBondState==" + device.getBondState()); return true; }
首先判断有没有拿到蓝牙适配器,然后判断地址是否拿到且正确,Gatt有没有获得(第一次连接肯定是没有的)。
接着通过地址获取远端的蓝牙设备,然后拿到对应设备的Gatt,所以说第一次连接获得了Gatt()并且绑定了回调函数mGattCallback,第二次连接会进入第二个if中,执行Gatt的conncet方法进行连接并判断连接结果。
/* 连接远程设备的回调函数 */ private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() { @Override public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) { String intentAction; if (newState == BluetoothProfile.STATE_CONNECTED)//连接成功 { intentAction = ACTION_GATT_CONNECTED; mConnectionState = STATE_CONNECTED; /* 通过广播更新连接状态 */ broadcastUpdate(intentAction); Log.i(TAG, "Connected to GATT server."); // Attempts to discover services after successful connection. Log.i(TAG, "Attempting to start service discovery:" + mBluetoothGatt.discoverServices()); } else if (newState == BluetoothProfile.STATE_DISCONNECTED)//连接失败 { intentAction = ACTION_GATT_DISCONNECTED; mConnectionState = STATE_DISCONNECTED; Log.i(TAG, "Disconnected from GATT server."); broadcastUpdate(intentAction); } } /* * 重写onServicesDiscovered,发现蓝牙服务 * * */ @Override public void onServicesDiscovered(BluetoothGatt gatt, int status) { if (status == BluetoothGatt.GATT_SUCCESS)//发现到服务 { broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED); Log.i(TAG, "--onServicesDiscovered called--"); } else { Log.w(TAG, "onServicesDiscovered received: " + status); System.out.println("onServicesDiscovered received: " + status); } } /* * 特征值的读写 * */ @Override public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) { if (status == BluetoothGatt.GATT_SUCCESS) { Log.i(TAG, "--onCharacteristicRead called--"); //从特征值读取数据 byte[] sucString = characteristic.getValue(); String string = new String(sucString); //将数据通过广播到Ble_Fragment broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } } /* * 特征值的改变 * */ @Override public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) { System.out.println("++++++++++++++++"); broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } /* * 特征值的写 * */ @Override public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) { Log.w(TAG, "--onCharacteristicWrite--: " + status); // 以下语句实现 发送完数据或也显示到界面上 broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } /* * 读描述值 * */ @Override public void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) { // TODO Auto-generated method stub // super.onDescriptorRead(gatt, descriptor, status); Log.w(TAG, "----onDescriptorRead status: " + status); byte[] desc = descriptor.getValue(); if (desc != null) { Log.w(TAG, "----onDescriptorRead value: " + new String(desc)); } } /* * 写描述值 * */ @Override public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) { // TODO Auto-generated method stub // super.onDescriptorWrite(gatt, descriptor, status); Log.w(TAG, "--onDescriptorWrite--: " + status); } /* * 读写蓝牙信号值 * */ @Override public void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status) { // TODO Auto-generated method stub // super.onReadRemoteRssi(gatt, rssi, status); Log.w(TAG, "--onReadRemoteRssi--: " + status); broadcastUpdate(ACTION_DATA_AVAILABLE, rssi); } @Override public void onReliableWriteCompleted(BluetoothGatt gatt, int status) { // TODO Auto-generated method stub // super.onReliableWriteCompleted(gatt, status); Log.w(TAG, "--onReliableWriteCompleted--: " + status); } };
广播更新状态:
//广播意图 private void broadcastUpdate(final String action, int rssi) { final Intent intent = new Intent(action); intent.putExtra(EXTRA_DATA, String.valueOf(rssi)); sendBroadcast(intent); } //广播意图 private void broadcastUpdate(final String action) { final Intent intent = new Intent(action); sendBroadcast(intent); } /* 广播远程发送过来的数据 */ public void broadcastUpdate(final String action, final BluetoothGattCharacteristic characteristic) { final Intent intent = new Intent(action); //从特征值获取数据 final byte[] data = characteristic.getValue(); if (data != null && data.length > 0) { final StringBuilder stringBuilder = new StringBuilder(data.length); for (byte byteChar : data) { stringBuilder.append(String.format("%02X ", byteChar)); Log.i(TAG, "***broadcastUpdate: byteChar = " + byteChar); } intent.putExtra(EXTRA_DATA, new String(data)); System.out.println("broadcastUpdate for read data:" + new String(data)); } sendBroadcast(intent); }
这里代码看上去非常多,但是主要就是对蓝牙终端的各种状态的响应,并且和Fragment中注册的广播接收器相配合,完成前后台的交接工作。
这里通过broadcastUpdate方法将不同状态的信息存入intent的EXTRA_DATA中,然后发送广播,与前面广播接收器的过滤器都是一一对应的,确保能够接收到。
该服务类还有几个其他方法,具体代码还是比较简单的,这里就直接贴在下面:
/** * @Title: disconnect * @Description: TODO(取消蓝牙连接) * @return void * @throws */ public void disconnect() { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.disconnect(); }
/** * After using a given BLE device, the app must call this method to ensure * resources are released properly. */ /** * @Title: close * @Description: TODO(关闭所有蓝牙连接) * @return void * @throws */ public void close() { if (mBluetoothGatt == null) { return; } mBluetoothGatt.close(); mBluetoothGatt = null; }
close就是直接关闭了,想要连接还需要重新获取Gatt
/** * @Title: readCharacteristic * @Description: TODO(读取特征值) * @param @param characteristic(要读的特征值) * @return void 返回类型 * @throws */ public void readCharacteristic(BluetoothGattCharacteristic characteristic) { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.readCharacteristic(characteristic); }// 写入特征值 public void writeCharacteristic(BluetoothGattCharacteristic characteristic) { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.writeCharacteristic(characteristic); } // 读取RSSi public void readRssi() { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.readRemoteRssi(); }