Android 测试手机与智能血压计BLE蓝牙扫描、连接、认证、断开的代码

以下是 Android 测试手机与智能血压计 BLE 蓝牙扫描、连接、认证、断开的代码示例，供参考：

首先，在 Manifest 中添加以下权限：

<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

然后，在代码中实现 BLE 相关功能：

private BluetoothAdapter mBluetoothAdapter;
private BluetoothLeScanner mBluetoothLeScanner;
private ScanCallback mScanCallback;
private BluetoothGatt mBluetoothGatt;

// 初始化 BLE 相关对象
private void initBluetooth() {
    // 获取蓝牙适配器
    mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    // 获取蓝牙扫描器
    mBluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner();
}

// 扫描 BLE 设备
private void startScan() {
    // 构建扫描过滤器
    ScanFilter scanFilter = new ScanFilter.Builder()
            .setDeviceName("BloodPressure") // 设置设备名称
            .setServiceUuid(ParcelUuid.fromString("00001810-0000-1000-8000-00805f9b34fb")) // 设置服务 UUID
            .build();
    // 构建扫描设置
    ScanSettings scanSettings = new ScanSettings.Builder()
            .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY) // 设置扫描模式
            .build();
    // 构建扫描回调
    mScanCallback = new ScanCallback() {
        @Override
        public void onScanResult(int callbackType, ScanResult result) {
            super.onScanResult(callbackType, result);
            // 获取设备地址
            String deviceAddress = result.getDevice().getAddress();
            // 停止扫描
            stopScan();
            // 连接设备
            connectDevice(deviceAddress);
        }
    };
    // 开始扫描
    mBluetoothLeScanner.startScan(Collections.singletonList(scanFilter), scanSettings, mScanCallback);
}

// 停止扫描 BLE 设备
private void stopScan() {
    mBluetoothLeScanner.stopScan(mScanCallback);
}

// 连接 BLE 设备
private void connectDevice(String deviceAddress) {
    // 获取设备对象
    BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(deviceAddress);
    // 连接设备
    mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
}

// GATT 回调
private BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        super.onConnectionStateChange(gatt, status, newState);
        if (newState == BluetoothProfile.STATE_CONNECTED) {
            // 连接成功，开始认证
            gatt.discoverServices();
        } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
            // 断开连接
            gatt.close();
        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        super.onServicesDiscovered(gatt, status);
        if (status == BluetoothGatt.GATT_SUCCESS) {
            // 获取服务对象
            BluetoothGattService service = gatt.getService(UUID.fromString("00001810-0000-1000-8000-00805f9b34fb"));
            if (service != null) {
                // 获取特征对象
                BluetoothGattCharacteristic characteristic = service.getCharacteristic(UUID.fromString("00002a35-0000-1000-8000-00805f9b34fb"));
                if (characteristic != null) {
                    // 设置特征通知
                    gatt.setCharacteristicNotification(characteristic, true);
                    // 获取描述对象
                    BluetoothGattDescriptor descriptor = characteristic.getDescriptor(UUID.fromString("00002902-0000-1000-8000-00805f9b34fb"));
                    if (descriptor != null) {
                        // 设置描述通知
                        descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
                        gatt.writeDescriptor(descriptor);
                    }
                }
            }
        }
    }

    @Override
    public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
        super.onCharacteristicChanged(gatt, characteristic);
        // 处理数据
        byte[] data = characteristic.getValue();
    }

    @Override
    public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
        super.onDescriptorWrite(gatt, descriptor, status);
        // 认证成功，开始接收数据
        if (status == BluetoothGatt.GATT_SUCCESS) {
            // 发送认证指令
            byte[] authCommand = {0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
            BluetoothGattService service = gatt.getService(UUID.fromString("00001810-0000-1000-8000-00805f9b34fb"));
            if (service != null) {
                BluetoothGattCharacteristic characteristic = service.getCharacteristic(UUID.fromString("00002a35-0000-1000-8000-00805f9b34fb"));
                if (characteristic != null) {
                    characteristic.setValue(authCommand);
                    gatt.writeCharacteristic(characteristic);
                }
            }
        }
    }
};

// 断开 BLE 设备连接
private void disconnectDevice() {
    if (mBluetoothGatt != null) {
        mBluetoothGatt.disconnect();
    }
}

以上代码实现了 BLE 设备的扫描、连接、认证和断开连接功能。其中，扫描时需要设置设备名称和服务 UUID，连接后需要发起服务发现、设置特征通知和描述通知，认证时需要发送认证指令，数据接收操作在 `onCharacteristicChanged` 方法中进行处理。