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android BLE 蓝牙的连接（二）

news 来源：原创 2024/9/20 13:42:54

下面是基于实际的项目得到的具体步骤及核心代码

1、权限问题

先判断手机是否满足android4.3以上版本，再判断手机是否开启蓝牙 主要涉及蓝牙权限和位置权限，注意不同android版本之间权限申请的差异，以及android权限动态申请和静态申请的区别

//动态申请权限相关
private String[] requestPermissionArray = new String[]{Manifest.permission.ACCESS_FINE_LOCATION,Manifest.permission.ACCESS_COARSE_LOCATION,//Manifest.permission.ACCESS_BACKGROUND_LOCATION,Manifest.permission.BLUETOOTH,Manifest.permission.BLUETOOTH_ADMIN,Manifest.permission.BLUETOOTH_SCAN,Manifest.permission.BLUETOOTH_ADVERTISE,Manifest.permission.BLUETOOTH_CONNECT,Manifest.permission.WRITE_EXTERNAL_STORAGE,Manifest.permission.READ_EXTERNAL_STORAGE
};/*** 初始化权限*/
public void initNeedPermissions() {/**Android 6.0以上动态申请权限*/if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){final PermissionRequest permissionRequest = new PermissionRequest();permissionRequest.requestRuntimePermission(MainActivity.this, requestPermissionArray, new PermissionListener() {@Overridepublic void onGranted() {Log.d(TAG,"所有权限已被授予");}/**用户勾选“不再提醒”拒绝权限后，关闭程序再打开程序只进入该方法！*/@Overridepublic void onDenied(List<String> deniedPermissions) {deniedPermissionList = deniedPermissions;for (String deniedPermission : deniedPermissionList) {Log.e(TAG,"被拒绝权限：" + deniedPermission);}}});}
}

 静态权限

    <uses-feature android:name="android.hardware.camera" /> <uses-feature android:name="android.hardware.camera.autofocus" /> <uses-permission android:name="android.permission.BLUETOOTH" /> <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" /><uses-permission android:name="android.permission.BLUETOOTH_SCAN" /><uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" /><uses-permission android:name="android.permission.READ_CONTACTS" /><uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /><uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> <uses-permission android:name="android.permission.INTERNET" />

2、 设备是否支持

使用蓝牙之前，首先要检查当前手机是否支持BLE蓝牙。 如果支持BLE蓝牙，检查手机蓝牙是否已开启。如果没有开启，则需要先打开蓝牙。打开手机蓝牙，有两种方式，一种是直接enable()打开，另外一种是提示用户打开，推荐第二种方式。

 /*** 检测手机是否支持4.0蓝牙* @param context  上下文* @return true--支持4.0  false--不支持4.0*/private boolean checkBle(Context context){if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {  //API 18 Android 4.3bluetoothManager = (BluetoothManager) context.getSystemService(Context.BLUETOOTH_SERVICE);if(bluetoothManager == null){return false;}bluetooth4Adapter = bluetoothManager.getAdapter();  //BLUETOOTH权限if(bluetooth4Adapter == null){return false;}else{Log.d(TAG,"该设备支持蓝牙4.0");return true;}}else{return false;}}
/*** 获取蓝牙状态*/public boolean isEnable(){if(bluetooth4Adapter == null){return false;}return bluetooth4Adapter.isEnabled();}/*** 打开蓝牙* @param isFast  true 直接打开蓝牙  false 提示用户打开*/public void openBluetooth(Context context,boolean isFast){if(!isEnable()){if(isFast){Log.d(TAG,"直接打开手机蓝牙");bluetooth4Adapter.enable();  //BLUETOOTH_ADMIN权限}else{Log.d(TAG,"提示用户去打开手机蓝牙");Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);context.startActivity(enableBtIntent);}}else{Log.d(TAG,"手机蓝牙状态已开");}}

3、搜索设备

搜索蓝牙：搜索蓝牙，回调接口中查看ble设备相关信息，一定时间停止扫描 扫描设备是耗时的操作，一旦扫描结束，就要及时停止扫描。

    //扫描设备//扫描设备回调@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)private BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {@Overridepublic void onLeScan(BluetoothDevice bluetoothDevice, int rssi, byte[] bytes) {//在onLeScan()回调中尽量做少的操作，可以将扫描到的设备扔到另一个线程中处理if(bluetoothDevice == null)return;if(bluetoothDevice.getName() != null){Log.d(TAG,bluetoothDevice.getName() + "-->" + bluetoothDevice.getAddress());}else{Log.d(TAG,"null" + "-->" + bluetoothDevice.getAddress());}BLEDevice bleDevice = new BLEDevice(bluetoothDevice,rssi);if(onDeviceSearchListener != null){onDeviceSearchListener.onDeviceFound(bleDevice);  //扫描到设备回调}}};/*** 设置时间段 扫描设备* @param onDeviceSearchListener  设备扫描监听* @param scanTime  扫描时间*/public void startDiscoveryDevice(OnDeviceSearchListener onDeviceSearchListener,long scanTime){if(bluetooth4Adapter == null){Log.e(TAG,"startDiscoveryDevice-->bluetooth4Adapter == null");return;}this.onDeviceSearchListener = onDeviceSearchListener;if(onDeviceSearchListener != null){onDeviceSearchListener.onDiscoveryStart();  //开始扫描回调}if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {Log.d(TAG,"开始扫描设备");bluetooth4Adapter.startLeScan(leScanCallback);}else{return;}//设定最长扫描时间mHandler.postDelayed(stopScanRunnable,scanTime);}private Runnable stopScanRunnable = new Runnable() {@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)@Overridepublic void run() {if(onDeviceSearchListener != null){onDeviceSearchListener.onDiscoveryOutTime();  //扫描超时回调}//scanTime之后还没有扫描到设备，就停止扫描。stopDiscoveryDevice();}};

4、建立连接

扫描到目标设备之后，开始建立连接 这里注意，连接之前一定要关闭扫描，否则会影响连接。BLE与经典蓝牙不同，经典蓝牙一旦建立连接，就可以进行数据通讯，而BLE建立连接之后，还需要发现系统服务，获取特定服务及读写特征。

（1）建立连接 & 发现系统服务

    //执行连接 //连接/通讯结果回调@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)private BluetoothGattCallback bluetoothGattCallback = new BluetoothGattCallback() {@Overridepublic void onPhyUpdate(BluetoothGatt gatt, int txPhy, int rxPhy, int status) {super.onPhyUpdate(gatt, txPhy, rxPhy, status);}@Overridepublic void onPhyRead(BluetoothGatt gatt, int txPhy, int rxPhy, int status) {super.onPhyRead(gatt, txPhy, rxPhy, status);}//连接状态回调-连接成功/断开连接@Overridepublic void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {super.onConnectionStateChange(gatt, status, newState);Log.d(TAG,"status:" + status);Log.d(TAG,"newState:" + newState);switch(status){case BluetoothGatt.GATT_SUCCESS:Log.w(TAG,"BluetoothGatt.GATT_SUCCESS");break;case BluetoothGatt.GATT_FAILURE:Log.w(TAG,"BluetoothGatt.GATT_FAILURE");break;case BluetoothGatt.GATT_CONNECTION_CONGESTED:Log.w(TAG,"BluetoothGatt.GATT_CONNECTION_CONGESTED");break;case BluetoothGatt.GATT_INSUFFICIENT_AUTHENTICATION:Log.w(TAG,"BluetoothGatt.GATT_INSUFFICIENT_AUTHENTICATION");break;case BluetoothGatt.GATT_INSUFFICIENT_ENCRYPTION:Log.w(TAG,"BluetoothGatt.GATT_INSUFFICIENT_ENCRYPTION");break;case BluetoothGatt.GATT_INVALID_OFFSET:Log.w(TAG,"BluetoothGatt.GATT_INVALID_OFFSET");break;case BluetoothGatt.GATT_READ_NOT_PERMITTED:Log.w(TAG,"BluetoothGatt.GATT_READ_NOT_PERMITTED");break;case BluetoothGatt.GATT_REQUEST_NOT_SUPPORTED:Log.w(TAG,"BluetoothGatt.GATT_REQUEST_NOT_SUPPORTED");break;}BluetoothDevice bluetoothDevice = gatt.getDevice();Log.d(TAG,"连接的设备：" + bluetoothDevice.getName() + "  " + bluetoothDevice.getAddress());isConnectIng = false;//移除连接超时mHandler.removeCallbacks(connectOutTimeRunnable);if(newState == BluetoothGatt.STATE_CONNECTED){Log.w(TAG,"连接成功");//连接成功去发现服务gatt.discoverServices();//设置发现服务超时时间mHandler.postDelayed(serviceDiscoverOutTimeRunnable,MAX_CONNECT_TIME);if(onBleConnectListener != null){onBleConnectListener.onConnectSuccess(gatt,bluetoothDevice,status);   //连接成功回调}}else if(newState == BluetoothGatt.STATE_DISCONNECTED) {//清空系统缓存ClsUtils.refreshDeviceCache(gatt);Log.e(TAG, "断开连接status:" + status);gatt.close();  //断开连接释放连接if(status == 133){//无法连接if(onBleConnectListener != null){onBleConnectListener.onConnectFailure(gatt,bluetoothDevice,"连接异常！",status);  //133连接异常 异常断开Log.e(TAG,"连接失败status：" + status + "  " + bluetoothDevice.getAddress());}}else if(status == 62){//成功连接没有发现服务断开if(onBleConnectListener != null){onBleConnectListener.onConnectFailure(gatt,bluetoothDevice,"连接成功服务未发现断开！",status); //62没有发现服务 异常断开Log.e(TAG,"连接成功服务未发现断开status:" + status);}}else if(status == 0){if(onBleConnectListener != null){onBleConnectListener.onDisConnectSuccess(gatt,bluetoothDevice,status); //0正常断开 回调}}else if(status == 8){//因为距离远或者电池无法供电断开连接// 已经成功发现服务if(onBleConnectListener != null){onBleConnectListener.onDisConnectSuccess(gatt,bluetoothDevice,status); //8断电断开  回调}}else if(status == 34){if(onBleConnectListener != null){onBleConnectListener.onDisConnectSuccess(gatt,bluetoothDevice,status); //34断开}}else {//其它断开连接if(onBleConnectListener != null){onBleConnectListener.onDisConnectSuccess(gatt,bluetoothDevice,status); //其它断开}}}else if(newState == BluetoothGatt.STATE_CONNECTING){Log.d(TAG,"正在连接...");if(onBleConnectListener != null){onBleConnectListener.onConnecting(gatt,bluetoothDevice);  //正在连接回调}}else if(newState == BluetoothGatt.STATE_DISCONNECTING){Log.d(TAG,"正在断开...");if(onBleConnectListener != null){onBleConnectListener.onDisConnecting(gatt,bluetoothDevice); //正在断开回调}}}//发现服务@Overridepublic void onServicesDiscovered(BluetoothGatt gatt, int status) {super.onServicesDiscovered(gatt, status);//移除发现服务超时mHandler.removeCallbacks(serviceDiscoverOutTimeRunnable);Log.d(TAG,"移除发现服务超时");Log.d(TAG,"发现服务");//获取特定服务及特征if(setupService(gatt,serviceUUID,readUUID,writeUUID)){if(onBleConnectListener != null){onBleConnectListener.onServiceDiscoverySucceed(gatt,gatt.getDevice(),status);  //成功发现服务回调}}else{if(onBleConnectListener != null){onBleConnectListener.onServiceDiscoveryFailed(gatt,gatt.getDevice(),"获取服务特征异常");  //发现服务失败回调}}}}@Overridepublic void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {super.onCharacteristicRead(gatt, characteristic, status);Log.d(TAG,"读status: " + status);}//向蓝牙设备写入数据结果回调@Overridepublic void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {super.onCharacteristicWrite(gatt, characteristic, status);if(characteristic.getValue() == null){Log.e(TAG,"characteristic.getValue() == null");return;}//将收到的字节数组转换成十六进制字符串String msg = TypeConversion.bytes2HexString(characteristic.getValue(),characteristic.getValue().length);if(status == BluetoothGatt.GATT_SUCCESS){//写入成功Log.w(TAG,"写入成功：" + msg);if(onBleConnectListener != null){onBleConnectListener.onWriteSuccess(gatt,gatt.getDevice(),characteristic.getValue());  //写入成功回调}}else if(status == BluetoothGatt.GATT_FAILURE){//写入失败Log.e(TAG,"写入失败：" + msg);if(onBleConnectListener != null){onBleConnectListener.onWriteFailure(gatt,gatt.getDevice(),characteristic.getValue(),"写入失败");  //写入失败回调}}else if(status == BluetoothGatt.GATT_WRITE_NOT_PERMITTED){//没有权限Log.e(TAG,"没有权限！");}}//读取蓝牙设备发出来的数据回调@Overridepublic void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {super.onCharacteristicChanged(gatt, characteristic);//接收数据byte[] bytes = characteristic.getValue();Log.w("TAG","收到数据str:" + TypeConversion.bytes2HexString(bytes,bytes.length));if(onBleConnectListener != null){onBleConnectListener.onReceiveMessage(gatt,gatt.getDevice(),characteristic,characteristic.getValue());  //接收数据回调}}@Overridepublic void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {super.onDescriptorRead(gatt, descriptor, status);}@Overridepublic void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {super.onDescriptorWrite(gatt, descriptor, status);}@Overridepublic void onReliableWriteCompleted(BluetoothGatt gatt, int status) {super.onReliableWriteCompleted(gatt, status);Log.d(TAG,"onReliableWriteCompleted");}@Overridepublic void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status) {super.onReadRemoteRssi(gatt, rssi, status);if(status == BluetoothGatt.GATT_SUCCESS){Log.w(TAG,"读取RSSI值成功，RSSI值：" + rssi + ",status" + status);if(onBleConnectListener != null){onBleConnectListener.onReadRssi(gatt,rssi,status);  //成功读取连接的信号强度回调}}else if(status == BluetoothGatt.GATT_FAILURE){Log.w(TAG,"读取RSSI值失败，status：" + status);}}//修改MTU值结果回调@Overridepublic void onMtuChanged(BluetoothGatt gatt, int mtu, int status) {super.onMtuChanged(gatt, mtu, status);///设置mtu值，即bluetoothGatt.requestMtu()时触发，提示该操作是否成功if(status == BluetoothGatt.GATT_SUCCESS){  //设置MTU成功  //MTU默认取的是23，当收到 onMtuChanged 后，会根据传递的值修改MTU，注意由于传输用掉3字节，因此传递的值需要减3。//mtu - 3Log.w(TAG,"设置MTU成功，新的MTU值：" + (mtu-3) + ",status" + status);if(onBleConnectListener != null){onBleConnectListener.onMTUSetSuccess("设置后新的MTU值 = " + (mtu-3) + "   status = " + status,mtu - 3);  //MTU设置成功}}else if(status == BluetoothGatt.GATT_FAILURE){  //设置MTU失败  Log.e(TAG,"设置MTU值失败：" + (mtu-3) + ",status" + status);if(onBleConnectListener != null){onBleConnectListener.onMTUSetFailure("设置MTU值失败：" + (mtu-3) + "   status：" + status);  //MTU设置失败}}}};/*** 通过蓝牙设备连接* @param context  上下文* @param bluetoothDevice  蓝牙设备* @param outTime          连接超时时间* @param onBleConnectListener  蓝牙连接监听者* @return*/@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)public BluetoothGatt connectBleDevice(Context context, BluetoothDevice bluetoothDevice, long outTime,OnBleConnectListener onBleConnectListener){if(bluetoothDevice == null){Log.e(TAG,"addBLEConnectDevice-->bluetoothDevice == null");return null;}this.onBleConnectListener = onBleConnectListener;this.curConnDevice = bluetoothDevice;Log.d(TAG,"开始准备连接：" + bluetoothDevice.getName() + "-->" + bluetoothDevice.getAddress());//出现 BluetoothGatt.android.os.DeadObjectException 蓝牙没有打开try{if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){mBluetoothGatt = bluetoothDevice.connectGatt(context, false, bluetoothGattCallback,BluetoothDevice.TRANSPORT_LE,BluetoothDevice.PHY_LE_1M_MASK);}else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {mBluetoothGatt = bluetoothDevice.connectGatt(context, false, bluetoothGattCallback,BluetoothDevice.TRANSPORT_LE);} else {mBluetoothGatt = bluetoothDevice.connectGatt(context, false, bluetoothGattCallback);}}catch(Exception e){Log.e(TAG,"e:" + e.getMessage());}mHandler.postDelayed(connectOutTimeRunnable,outTime);return mBluetoothGatt;}//连接超时private Runnable connectOutTimeRunnable = new Runnable() {@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)@Overridepublic void run() {if(mBluetoothGatt == null){Log.e(TAG,"connectOuttimeRunnable-->mBluetoothGatt == null");return;}isConnectIng = false;mBluetoothGatt.disconnect();//连接超时当作连接失败回调if(onBleConnectListener != null){onBleConnectListener.onConnectFailure(mBluetoothGatt,curConnDevice,"连接超时！",-1);  //连接失败回调}}};//发现服务超时private Runnable serviceDiscoverOutTimeRunnable = new Runnable() {@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)@Overridepublic void run() {if(mBluetoothGatt == null){Log.e(TAG,"connectOuttimeRunnable-->mBluetoothGatt == null");return;}isConnectIng = false;mBluetoothGatt.disconnect();//发现服务超时当作连接失败回调if(onBleConnectListener != null){onBleConnectListener.onConnectFailure(mBluetoothGatt,curConnDevice,"发现服务超时！",-1);  //连接失败回调}}};

 2）发现系统服务之后，还需要获取特定服务及读写特征才能进行数据通讯。 一般，读特征是用来读取蓝牙设备发出来的数据，写特征是向蓝牙设备写入数据，其中，读特征一定要设置打开通知，否则接收不到消息。

/*** 获取特定服务及特征* 1个serviceUUID -- 1个readUUID -- 1个writeUUID* @param bluetoothGatt* @param serviceUUID* @param readUUID* @param writeUUID* @return*/@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)private boolean setupService(BluetoothGatt bluetoothGatt,String serviceUUID,String readUUID,String writeUUID) {if (bluetoothGatt == null) {Log.e(TAG, "setupService()-->bluetoothGatt == null");return false;}if(serviceUUID == null){Log.e(TAG, "setupService()-->serviceUUID == null");return false;}for (BluetoothGattService service : bluetoothGatt.getServices()) {
//            Log.d(TAG, "service = " + service.getUuid().toString());if (service.getUuid().toString().equals(serviceUUID)) {bluetoothGattService = service;}}//通过上面方法获取bluetoothGattService
//        bluetoothGattService = bleManager.getBluetoothGattService(bluetoothGatt,ConsData.MY_BLUETOOTH4_UUID);if (bluetoothGattService == null) {Log.e(TAG, "setupService()-->bluetoothGattService == null");return false;}Log.d(TAG, "setupService()-->bluetoothGattService = " + bluetoothGattService.toString());if(readUUID == null || writeUUID == null){Log.e(TAG, "setupService()-->readUUID == null || writeUUID == null");return false;}for (BluetoothGattCharacteristic characteristic : bluetoothGattService.getCharacteristics()) {if (characteristic.getUuid().toString().equals(readUUID)) {  //读特征readCharacteristic = characteristic;} else if (characteristic.getUuid().toString().equals(writeUUID)) {  //写特征writeCharacteristic = characteristic;}}if (readCharacteristic == null) {Log.e(TAG, "setupService()-->readCharacteristic == null");return false;}if (writeCharacteristic == null) {Log.e(TAG, "setupService()-->writeCharacteristic == null");return false;}//打开读通知enableNotification(true, bluetoothGatt, readCharacteristic);//重点中重点，需要重新设置List<BluetoothGattDescriptor> descriptors = readCharacteristic.getDescriptors();for (BluetoothGattDescriptor descriptor : descriptors) {descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);bluetoothGatt.writeDescriptor(descriptor);}//延迟2s，保证所有通知都能及时打开mHandler.postDelayed(new Runnable() {@Overridepublic void run() {}}, 2000);return true;}//  打开通知/*** 设置读特征接收通知* @param enable  为true打开通知* @param gatt    连接* @param characteristic  特征*/@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)public void enableNotification(boolean enable, BluetoothGatt gatt, BluetoothGattCharacteristic characteristic){if(gatt == null){Log.e(TAG,"enableNotification-->gatt == null");return;}if(characteristic == null){Log.e(TAG,"enableNotification-->characteristic == null");return;}//这一步必须要有，否则接收不到通知gatt.setCharacteristicNotification(characteristic,enable);}

5、数据通讯

（1）发送数据 mBluetoothGatt.writeCharacteristic()方法的返回值，并不能真正的表示数据是否发送成功，而是通过BluetoothGattCallback回调方法onCharacteristicWrite()来判断数据是否已成功写入底层。

 //向蓝牙设备写入数据结果回调@Overridepublic void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {super.onCharacteristicWrite(gatt, characteristic, status);if(characteristic.getValue() == null){Log.e(TAG,"characteristic.getValue() == null");return;}//将收到的字节数组转换成十六进制字符串String msg = TypeConversion.bytes2HexString(characteristic.getValue(),characteristic.getValue().length);if(status == BluetoothGatt.GATT_SUCCESS){//写入成功Log.w(TAG,"写入成功：" + msg);if(onBleConnectListener != null){onBleConnectListener.onWriteSuccess(gatt,gatt.getDevice(),characteristic.getValue());  //写入成功回调}}else if(status == BluetoothGatt.GATT_FAILURE){//写入失败Log.e(TAG,"写入失败：" + msg);if(onBleConnectListener != null){onBleConnectListener.onWriteFailure(gatt,gatt.getDevice(),characteristic.getValue(),"写入失败");  //写入失败回调}}else if(status == BluetoothGatt.GATT_WRITE_NOT_PERMITTED){//没有权限Log.e(TAG,"没有权限！");}}
///  发送数据  ////*** 发送消息  byte[]数组* @param msg  消息* @return  true  false*/@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)public boolean sendMessage( byte[] msg){if(writeCharacteristic == null){Log.e(TAG,"sendMessage(byte[])-->writeGattCharacteristic == null");return false;}if(mBluetoothGatt == null){Log.e(TAG,"sendMessage(byte[])-->mBluetoothGatt == null");return false;}boolean  b = writeCharacteristic.setValue(msg);Log.d(TAG, "写特征设置值结果：" + b);return mBluetoothGatt.writeCharacteristic(writeCharacteristic);}

 （2）接收数据 接收的数据是直接通过BluetoothGattCallback回调方法onCharacteristicChanged()来获取的。

//读取蓝牙设备发出来的数据回调@Overridepublic void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {super.onCharacteristicChanged(gatt, characteristic);//接收数据byte[] bytes = characteristic.getValue();Log.w("TAG","收到数据str:" + TypeConversion.bytes2HexString(bytes,bytes.length));if(onBleConnectListener != null){onBleConnectListener.onReceiveMessage(gatt,gatt.getDevice(),characteristic,characteristic.getValue());  //接收数据回调}}

 6、断开连接

BLE通讯结束之后，需要及时断开连接,并且在断开连接的回调处释放资源。否则会导致下一次执行连接操作时，导致133异常。所以，一般连接出现133异常，都是因为断开后及时释放资源。

断开连接的结果是在BluetoothGattCallback回调方法onConnectionStateChange()来获取的。（可查看上面建立连接处的代码）

 ///  断开连接  ////*** 断开连接*/@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)public void disConnectDevice(){if(mBluetoothGatt == null){Log.e(TAG,"disConnectDevice-->bluetoothGatt == null");return;}//系统断开mBluetoothGatt.disconnect();}

 7、过程中遇到过的实际问题

暂无

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