如何通過BluetoothGatt在兩部Android手機中相互通信

Question

在服務器端，我設置：

val bluetoothLeAdvertiser: BluetoothLeAdvertiser = mBleAdapter!!.bluetoothLeAdvertiser
    bluetoothLeAdvertiser.startAdvertising(settings, advertiseData, scanResponseData, callback)
}

private var mGattServer:BluetoothGattServer? = null
private fun initServices() {
    mGattServer = mBleManager?.openGattServer(this, gattServerCallback) as BluetoothGattServer
    val gattService = BluetoothGattService(Constants.BLE_SERVICE_UUID, BluetoothGattService.SERVICE_TYPE_PRIMARY)
    val characteristicRead = BluetoothGattCharacteristic(Constants.BLE_READ_UUID, BluetoothGattCharacteristic.PROPERTY_READ, BluetoothGattCharacteristic.PERMISSION_READ)
    val descriptor = BluetoothGattDescriptor(Constants.BLE_DESC_UUID, BluetoothGattCharacteristic.PERMISSION_WRITE)
    characteristicRead.addDescriptor(descriptor)
    gattService.addCharacteristic(characteristicRead)
    val characteristicWrite = BluetoothGattCharacteristic(Constants.BLE_WRITE_UUID, BluetoothGattCharacteristic.PROPERTY_WRITE or
            BluetoothGattCharacteristic.PROPERTY_READ or BluetoothGattCharacteristic.PROPERTY_NOTIFY,
            BluetoothGattCharacteristic.PERMISSION_WRITE)
    gattService.addCharacteristic(characteristicWrite)
    mGattServer?.addService(gattService)
}

和 UUIDS 定義為：

val BLE_SERVICE_UUID = UUID.fromString("00001802-0000-1000-8000-00805f9b34fb")
val BLE_WRITE_UUID = UUID.fromString("00002a02-0000-1000-8000-00805f9b34fb")
val BLE_READ_UUID  = UUID.fromString("00002a03-0000-1000-8000-00805f9b34fb")
val BLE_DESC_UUID  = UUID.fromString("00002a04-0000-1000-8000-00805f9b34fb")

並且在運行服務器應用程序時，它會打印 onServiceAdded:status=0，這意味着該服務已添加成功。

但是當客戶端應用程序連接到 GattServer 並打印所有服務中的所有特征時，我發現：

Connected to GATT server.
SUUID:00001801-0000-1000-8000-00805f9b34fb
CUUID:00002a05-0000-1000-8000-00805f9b34fb Properties:32
SUUID:00001800-0000-1000-8000-00805f9b34fb
CUUID:00002a00-0000-1000-8000-00805f9b34fb Properties:2
CUUID:00002a01-0000-1000-8000-00805f9b34fb Properties:2
CUUID:00002aa6-0000-1000-8000-00805f9b34fb Properties:2

沒有與我在服務器端設置的 UUID 相同的 UUID，並且沒有 UUID 具有 BluetoothGattCharacteristic.PERMISSION_WRITE 的屬性。

為什么？ 如何將數據從客戶端發送到服務器？

Answer 1

掃描使用以下代碼，可以得到正確的結果：

List<ScanFilter> filters = new ArrayList<>();
    ScanFilter scanFilter = new ScanFilter.Builder()
            .setServiceUuid(new ParcelUuid(Constants.SERVICE_UUID))
            .build();
    filters.add(scanFilter);
    ScanSettings settings = new ScanSettings.Builder()
            .setScanMode(ScanSettings.SCAN_MODE_LOW_POWER)
            .build();
    /*mScanResults = new HashMap<>();
    mScanCallback = new BtleScanCallback(mScanResults);*/
    mScanCallback = new BtleScanCallback();
    mBluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner();
    mBluetoothLeScanner.startScan(filters, settings, mScanCallback);