如何获取特征Uuid？

Question

我使用 RxAndroidBle https://github.com/Polidea/RxAndroidBle 库来处理 ble 设备。但是我在查找 characteristicUuid.

时遇到问题

我从 README 做了所有的事情，但是找不到 characteristicUuid。在read()中需要执行.flatMapSingle { rxBleConnection -> rxBleConnection.readCharacteristic(characteristicUuid) }，但是没有characteristicUuid。我在哪里可以买到它？

private lateinit var rxBleClient: RxBleClient
    private lateinit var bleDevice: RxBleDevice
    private lateinit var characteristicUuid: UUID

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    getLocationPermission()

    rxBleClient = RxBleClient.create(this)

    val enableBtIntent = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
    startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT)

    button.setOnClickListener { discover() }
}

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    if (requestCode == REQUEST_ENABLE_BT && resultCode == Activity.RESULT_OK) {
    }
}

private lateinit var scanSubscription: Disposable

private fun discover() {
    Log.i("BLE", "start scan")
    scanSubscription = rxBleClient.scanBleDevices(
        ScanSettings.Builder()
            // .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY) // change if needed
            // .setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES) // change if needed
            .build()
        // add filters if needed
    )
        .subscribe(
            { scanResult ->
                bleDevice = scanResult.bleDevice
                Log.i("BLE", "SCAN ${bleDevice.name} ${bleDevice.macAddress}")
                connect()
                scanSubscription.dispose()
                // Process scan result here.
            },
            { throwable ->
                Log.i("BLE", "ERROR SCAN ${throwable.localizedMessage}")
                // Handle an error here.
            }
        )

}

private lateinit var connectDisposable: Disposable

private fun connect() {
    val device = bleDevice

    connectDisposable = device.establishConnection(false) // <-- autoConnect flag
        .subscribe(
            { rxBleConnection ->
                Log.i("BLE", "CONNECT ${rxBleConnection.mtu}")
                read(device)
                connectDisposable.dispose()
                // All GATT operations are done through the rxBleConnection.
            },
            { throwable ->
                Log.i("BLE", "ERROR CONNECT ${throwable.localizedMessage}")
                // Handle an error here.
            }
        )

}

private fun read(device: RxBleDevice) {
    val dis = device.establishConnection(false)
        .flatMapSingle { rxBleConnection -> rxBleConnection.readCharacteristic(characteristicUuid) }
        .subscribe(
            { characteristicValue ->
                Log.i("BLE", "READ $characteristicValue")
                // Read characteristic value.
            },
            { throwable ->
                Log.i("BLE", "ERROR READ ${throwable.localizedMessage}")
                // Handle an error here.
            }
        )
}

Answer 1

制造商关于您正在使用的蓝牙设备的 manual/info 可能应该提及特性的 UUID。根据我的经验，我们的团队有一位工程师，他为我们提供了有关设备的 ble 服务和特性及其 UUID 的文档。

您可以使用以下代码获取您设备中的所有 ble 服务、特征及其 UUID

rxBleConnection.discoverServices()
   .map(rxBleDeviceServices -> {
      List<BluetoothGattService> services = rxBleDeviceServices.getBluetoothGattServices();

      for (BluetoothGattService service : services) {
         // here you can work with service's uuid
         String serviceUuid = service.getUuid().toString();

         // or with all characteristics in service
         List<BluetoothGattCharacteristic> characteristics = service.getCharacteristics();

         for (BluetoothGattCharacteristic characteristic : characteristics) {
            // here you have your characteristic's UUID
            String characteristicUuid = characteristic.getUuid().toString();
         }
   });

然后保存找到的 BluetoothGattCharacteristic 或 UUID 之一并将其传递给 rxBleConnection.readCharacteristic(bluetoothGattCharacteristic)

如何获取特征Uuid？

How to get characteristicUuid?

android

kotlin

bluetooth-lowenergy

rxandroidble