• BlueTooth

    本文主要介绍，蓝牙开启、蓝牙扫描、配对，建立链接，进行通信。

    1.声明权限：

    1.   
    2.     <uses-permission android:name="android.permission.INTERNET" />
    3.     
    4.     <uses-permission android:name="android.permission.BLUETOOTH" />
    5.     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    6.     
    7.     
    8.     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    9.     <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
    10.     
    11.     <uses-permission android:name="android.permission.BLUETOOTH_CONNECT"/>
    12.     
    13.     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    2.获取蓝牙适配器：

    1.  // 获取蓝牙配置器 BluetoothAdapter 方式1.
    2.         BluetoothManager bluetoothManger =
    3.                 (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
    4.         bluetoothAdapter = bluetoothManger.getAdapter();
    5.          //方式2
    6. //        bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

    3.开启蓝牙：

    1. if (!bluetoothAdapter.isEnabled()) {
    2.             // 没有开启蓝牙 开启蓝牙
    3.             Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
    4.             startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
    5.         }

     

    4.动态申请权限：

    1.   //判断是否有访问位置的权限，没有权限，直接申请位置权限
    2.         if ((checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
    3.                 || (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)) {
    4.             requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION, Manifest.permission.ACCESS_FINE_LOCATION}, 200);
    5.         }

    5.创建蓝牙结果列表，并添加点击事件。

    1.  // 创建设备列表适配器
    2.         deviceListAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1);
    3.         deviceListView = (ListView) findViewById(R.id.device_list);
    4.         deviceListView.setAdapter(deviceListAdapter);
    5.         deviceListView.setOnItemClickListener((adapterView, view, i, l) -> {
    6.             if (bluetoothAdapter.isDiscovering()) {
    7.                 bluetoothAdapter.cancelDiscovery();
    8.             }
    9.             String deviceName = deviceListAdapter.getItem(i);
    10.             Log.e("nyz", "deviceName " + deviceName);
    11.             selectedDevice = bluetoothAdapter.getRemoteDevice(deviceName.split("\\n")[1]);
    12.             Log.e("nyz", "name " + selectedDevice.getName());
    13.             Log.e("nyz", "address " + selectedDevice.getAddress());
    14.             ParcelUuid[] uuids = selectedDevice.getUuids();
    15.             for (int index = 0; index < uuids.length; index++) {
    16.                 Log.e("nyz", "uuids " + uuids[index]);
    17.             }
    18.             connectToDevice(selectedDevice);
    19.         });

    6.创建广播接受者，用于接收扫描到蓝牙后的结果。

       

    1.  
    2.     @SuppressLint("MissingPermission")
    3.     private final BroadcastReceiver deviceReceiver = new BroadcastReceiver() {
    4.         @Override
    5.         public void onReceive(Context context, Intent intent) {
    6.             String action = intent.getAction();
    7.             Log.e("nyz", "action " + action);
    8.             // 当有新设备被发现时
    9.             if (BluetoothDevice.ACTION_FOUND.equals(action)) {
    10.                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
    11.                 deviceListAdapter.notifyDataSetChanged();
    12.                 if (!TextUtils.isEmpty(device.getName())) {
    13.                     deviceListAdapter.add(device.getName() + "\n" + device.getAddress());
    14.                 }
    15.             }
    16.             // 做配对使用
    17.             else if (BluetoothDevice.ACTION_PAIRING_REQUEST.equals(action)) {
    18.                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
    19.                 int pairingVariant = intent.getIntExtra(BluetoothDevice.EXTRA_PAIRING_VARIANT, BluetoothDevice.ERROR);
    20.                 // 如果需要 PIN 码，可以在这里自动输入
    21.                 if (pairingVariant == BluetoothDevice.PAIRING_VARIANT_PIN) {
    22.                     device.setPin("1234".getBytes()); // 替换为您的 PIN 码
    23.                 }
    24.  
    25.                 // 如果需要用户确认配对请求，可以在这里显示对话框来请求用户确认
    26.             } else if (BluetoothDevice.ACTION_BOND_STATE_CHANGED.equals(action)) {
    27.                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
    28.                 int bondState = intent.getIntExtra(BluetoothDevice.EXTRA_BOND_STATE, BluetoothDevice.ERROR);
    29.                 int previousBondState = intent.getIntExtra(BluetoothDevice.EXTRA_PREVIOUS_BOND_STATE, BluetoothDevice.ERROR);
    30.                 // 配对状态改变的处理逻辑
    31.                 if (bondState == BluetoothDevice.BOND_BONDED && previousBondState == BluetoothDevice.BOND_BONDING) {
    32.  
    33.                     // 配对成功
    34.                 } else if (bondState == BluetoothDevice.BOND_NONE && previousBondState == BluetoothDevice.BOND_BONDED) {
    35.                     // 配对解除
    36.                 }
    37.             } else if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
    38.                 Log.e("nyz", "搜索开始..");
    39.             } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
    40.                 Log.e("nyz", "搜索结束..");
    41.             } else if (BluetoothAdapter.ACTION_CONNECTION_STATE_CHANGED.equals(action)) {
    42.                 int state = intent.getIntExtra(BluetoothAdapter.EXTRA_CONNECTION_STATE, BluetoothAdapter.ERROR);
    43.  
    44.                 if (state == BluetoothAdapter.STATE_CONNECTING) {
    45.                     Log.e("nyz", "正在链接...");
    46.                 } else if (state == BluetoothAdapter.STATE_CONNECTED) {
    47. //                    Log.e("nyz", "链接成功...");
    48. //                    InputStream inputStream = null;
    49. //                    try {
    50. //                        inputStream = bluetoothSocket.getInputStream();
    51. //                        OutputStream outputStream = bluetoothSocket.getOutputStream();
    52. //                        Log.e("nyz", "inputStream " + (inputStream != null));
    53. //                        Log.e("nyz", "outputStream " + (outputStream != null));
    54. //                        Log.e("nyz", "获取流成功..");
    55. //                    } catch (IOException e) {
    56. //                        e.printStackTrace();
    57. //                    }
    58.  
    59.                 } else if (state == BluetoothAdapter.STATE_DISCONNECTED) {
    60.                     Log.e("nyz", "断开链接...");
    61.                 }
    62.             }
    63.         }
    64.     };

    7.注册和反注册：

      

    1.   // 注册广播
    2.     public void registerBroadcast() {
    3.         // 注册广播接收器
    4.         IntentFilter intent = new IntentFilter();
    5.         intent.addAction(BluetoothDevice.ACTION_FOUND);//搜索发现设备
    6.         intent.addAction(BluetoothDevice.ACTION_BOND_STATE_CHANGED);//状态改变
    7.         intent.addAction(BluetoothDevice.ACTION_PAIRING_REQUEST);//配对请求
    8.         intent.addAction(BluetoothAdapter.ACTION_SCAN_MODE_CHANGED);//行动扫描模式改变了
    9.         intent.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);//动作状态发生了变化
    10.         intent.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);//搜索结束
    11.         intent.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);//开始搜索
    12.         intent.addAction(BluetoothAdapter.ACTION_CONNECTION_STATE_CHANGED);//链接状态变化
    13.         registerReceiver(deviceReceiver, intent);
    14.     }
    15.  
    16.     @Override
    17.     protected void onDestroy() {
    18.         super.onDestroy();
    19.         // 取消注册广播接收器
    20.         unregisterReceiver(deviceReceiver);
    21.     }

    8.开始搜索附近蓝牙设备：

         bluetoothAdapter.startDiscovery，搜索结束后，会通过广播的形式来接收。

    bluetoothAdapter.getBondedDevices() 返回的是已经配对过的蓝牙设备列表。  

    1.  private void startDeviceDiscovery() {
    2.  
    3.         deviceListAdapter.clear();
    4.         int state = bluetoothAdapter.getState();
    5.         Log.e("nyz", "state " + state);
    6.         boolean b = bluetoothAdapter.startDiscovery();
    7.         Log.e("nyz", "bluetooth state " + b);
    8.         //获取已经连接过的设备。
    9.         Set<BluetoothDevice> bondedDevices = bluetoothAdapter.getBondedDevices();
    10.         for (BluetoothDevice device : bondedDevices) {
    11.             Log.e("nyz", "device  " + device.getName());
    12.             deviceListAdapter.add(device.getName() + "\n" + device.getAddress());
    13.             deviceListAdapter.notifyDataSetChanged();
    14.         }
    15.  
    16.     }

    9.附近蓝牙设备结果：添加到列表中。

    1.  // 当有新设备被发现时
    2.             if (BluetoothDevice.ACTION_FOUND.equals(action)) {
    3.                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
    4.                 deviceListAdapter.notifyDataSetChanged();
    5.                 if (!TextUtils.isEmpty(device.getName())) {
    6.                     deviceListAdapter.add(device.getName() + "\n" + device.getAddress());
    7.                 }
    8.             }

    10.点击列表中的蓝牙进行配对链接，没有配对过的需要配对，已经配对过的，可以直接链接。

          1）点击事件

    1.  deviceListView.setOnItemClickListener((adapterView, view, i, l) -> {
    2.             //当点击某个蓝牙列表时，需要停止扫描，减少性能的消耗
    3.             if (bluetoothAdapter.isDiscovering()) {
    4.                 bluetoothAdapter.cancelDiscovery();
    5.             }
    6.             String deviceName = deviceListAdapter.getItem(i);
    7.             Log.e("nyz", "deviceName " + deviceName);
    8.             selectedDevice = bluetoothAdapter.getRemoteDevice(deviceName.split("\\n")[1]);
    9.             Log.e("nyz", "name " + selectedDevice.getName());
    10.             Log.e("nyz", "address " + selectedDevice.getAddress());
    11.             ParcelUuid[] uuids = selectedDevice.getUuids();
    12.             for (int index = 0; index < uuids.length; index++) {
    13.                 Log.e("nyz", "uuids " + uuids[index]);
    14.             }
    15.             //开始链接
    16.             connectToDevice(selectedDevice);
    17.         });

       2）开始配对链接：

         需要放在子线程中执行。

    1.   @SuppressLint("MissingPermission")
    2.     private void connectToDevice(BluetoothDevice device) {
    3.         new Thread() {
    4.             @Override
    5.             public void run() {
    6.                 super.run();
    7.                 UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); // SPP UUID for serial communication
    8.                 try {
    9.                     // 进行配对
    10.                     if (!(device.getBondState() == BluetoothDevice.BOND_BONDED)) {
    11.                         Log.e("nyz", "等待配对");
    12.                         boolean success = device.createBond();
    13.                         Log.e("nyz", "配对结果 " + success);
    14.                     } else {
    15.                         Log.e("nyz", "已经配对过");
    16.                     }
    17.                     // 等待配对完成
    18.  
    19. //            Thread.sleep(500);
    20.                     Log.e("nyz", "创建 socket");
    21.                     bluetoothSocket = device.createRfcommSocketToServiceRecord(uuid);
    22.                     Log.e("nyz", "connect...");
    23.                     if (bluetoothSocket == null) {
    24.                         Log.e("nyz", "connect...failed");
    25.                         return;
    26.                     } else {
    27.                         Log.e("nyz", "socket 创建成功");
    28.                     }
    29.                     new Thread() {
    30.                         @Override
    31.                         public void run() {
    32.                             super.run();
    33.  
    34.                             try {
    35.                                 bluetoothSocket.connect();
    36.                                 // 成功连接
    37.                                 Log.e("nyz", "链接成功...");
    38.                                 InputStream inputStream = bluetoothSocket.getInputStream();
    39.                                 OutputStream outputStream = bluetoothSocket.getOutputStream();
    40.                                 Log.e("nyz", "inputStream " + (inputStream != null));
    41.                                 Log.e("nyz", "outputStream " + (outputStream != null));
    42.                             } catch (Exception e) {
    43.                                 e.printStackTrace();
    44.                             }
    45.  
    46.                         }
    47.                     }.start();
    48.                 } catch (Exception e) {
    49.                     Log.e("nyz", "conn failed");
    50.                     e.printStackTrace();
    51.                 }
    52.             }
    53.         }.start();
    54.     }

     配对成功后， bluetoothSocket = device.createRfcommSocketToServiceRecord(uuid);

    拿到一个一个Socket对象。

    开始链接：

    1.   bluetoothSocket.connect();
    2.                                 // 成功连接
    3.                                 Log.e("nyz", "链接成功...");
    4.                                 InputStream inputStream = bluetoothSocket.getInputStream();
    5.                                 OutputStream outputStream = bluetoothSocket.getOutputStream();
    6.                                 Log.e("nyz", "inputStream " + (inputStream != null));
    7.                                 Log.e("nyz", "outputStream " + (outputStream != null));

    链接成功后，可以从socket中拿到输入输出流，这样就可以和另外一台设计进行通信了。

    和串口类似，串口通信，也是拿到一个输入输出流。

    蓝牙通信官方文档：

    蓝牙概览  |  Connectivity  |  Android Developers

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  • 原文地址：https://blog.csdn.net/niuyongzhi/article/details/133773269