似乎已设置 BLE 通知，但在 Android 上未收到任何通知

Question

我有一个尝试接收 BLE 通知的 Android 应用程序。 通知发送到 iPhone，因此它似乎是设置问题，而不是 GATT 服务器问题。

在 Android 应用程序中，我正在执行以下操作，在我过去的经验中，这是所有需要的。

1) 将通知特性写入类型设置为 2（写入类型默认）。

2）将通知特性设置为true

3）将描述符设置为true

4）这不应该是必需的，但我有时读过它，我读过特征

这是我的日志的示例输出：

GattCallback: BLE-Setting up notifications if possible

GattCallback: BLE-Attempting to find matching characteristics for notification setup
com.android.myapp I/BLEUtilsKt: BLE-Matching service found for service: 4880c12c-fdcb-4077-8920-a450d7f9b907

GattCallback: BLE-State set to: READ_CHARACTERISTIC

GattCallback: BLE-Notify changed. State is now set to: READ_CHARACTERISTIC

GattCallback: BLE-Setting write type on notification characteristic: FEC26EC4-6D71-4442-9F81-55BC21D658D6. Write type is: 2 (WRITE_TYPE_DEFAULT)

GattCallback: BLE-Attempting to set notification characteristic fec26ec4-6d71-4442-9f81-55bc21d658d6 to true

GattCallback: BLE-Characteristic notification set successfully for FEC26EC4-6D71-4442-9F81-55BC21D658D6

GattCallback: BLE-Now setting its descriptor: FEC26EC4-6D71-4442-9F81-55BC21D658D6

GattCallback: BLE-Enabling Client Characteristic Configuration Descriptor for characteristic: fec26ec4-6d71-4442-9f81-55bc21d658d6

GattCallback: BLE-Characteristic Configuration Descriptor write initiated on: 00002902-0000-1000-8000-00805f9b34fb

BleHandler: BLE-Read characteristic being set to: android.bluetooth.BluetoothGattCharacteristic@48fd37c

GattCallback: BLE-Descriptor 00002902-0000-1000-8000-00805F9B34FB written successfully as value [1, 0]

BleHandler: BLE-Priming the pump on GATT: android.bluetooth.BluetoothGatt@d54f120 on read characteristic: android.bluetooth.BluetoothGattCharacteristic@48fd37c

GattCallback: BLE-onCharacteristic Read hit

GattCallback: BLE-Characteristic read successfully. Entering decipherCharacteristicValue

我一定是遗漏了一些东西，但我在这里所做的在过去是有效的。 谁能看到我做错了什么？

如果有帮助，这是原始代码

private fun setUpNotifications() {

    Timber.i("BLE-Setting up notifications if possible")

    if(mBluetoothGatt == null) {
        Timber.w("BLE-Set up notifications attempted but gatt is still null")
        return
    }

    Timber.i("BLE-Attempting to find matching characteristics for notification setup")
    val matchingCharacteristics = findCharacteristics(mBluetoothGatt!!)

    mState = BleHandler.ConnectionState.READ_CHARACTERISTIC

    Timber.i("BLE-State set to: $mState")

    notifyChanged()

    if(matchingCharacteristics.isEmpty()) {
        Timber.w("BLE-NO MATCHING CHARACTERISTICS FOUND")
        return
    }

    for (characteristic in matchingCharacteristics) {
        characteristic.writeType = BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT
        Timber.i("BLE-Setting write type on notification characteristic: ${characteristic.uuid.toString().toUpperCase(Locale.getDefault())}. Write type is: ${characteristic.writeType} (WRITE_TYPE_DEFAULT)")
        enableCharacteristicNotification(mBluetoothGatt!!, characteristic)

        Timber.i("BLE-Now setting its descriptor: ${characteristic.uuid.toString().toUpperCase(Locale.getDefault())}")
        enableCharacteristicConfigurationDescriptor(mBluetoothGatt!!, characteristic)
        mClientActionListener.setReadCharacteristic(characteristic)
    }
}

    private fun enableCharacteristicNotification(gatt: BluetoothGatt, characteristic: BluetoothGattCharacteristic) {
    Timber.i("BLE-Attempting to set notification characteristic ${characteristic.uuid.toString()} to true")
    val characteristicWriteSuccess = gatt.setCharacteristicNotification(characteristic, true)

    if (characteristicWriteSuccess) {
        Timber.i("BLE-Characteristic notification set successfully for " + characteristic.uuid.toString().toUpperCase(Locale.getDefault()))
    }
    else {
        Timber.e("BLE-Characteristic notification set failure for " + characteristic.uuid.toString().toUpperCase(Locale.getDefault()))
    }
}

private fun enableCharacteristicConfigurationDescriptor(gatt: BluetoothGatt, characteristic: BluetoothGattCharacteristic) {
    Timber.i("BLE-Enabling Client Characteristic Configuration Descriptor for characteristic: ${characteristic.uuid}")

    val descriptorList = characteristic.descriptors
    val descriptor = findClientConfigurationDescriptor(descriptorList)

    if (descriptor == null) {
        Timber.e("BLE-Unable to find Characteristic Configuration Descriptor")
        return
    }

    descriptor.value = BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE
    val descriptorWriteInitiated = gatt.writeDescriptor(descriptor)

    if (descriptorWriteInitiated) {
        Timber.i("BLE-Characteristic Configuration Descriptor write initiated on: " + descriptor.uuid.toString())
    }
    else {
        Timber.e("BLE-Characteristic Configuration Descriptor write failed to initiate: " + descriptor.uuid.toString())
    }
}

override fun onCharacteristicChanged(gatt: BluetoothGatt, characteristic: BluetoothGattCharacteristic) {
    super.onCharacteristicChanged(gatt, characteristic)
    Timber.i("BLE-Characteristic change detected, " + characteristic.uuid.toString())
    decipherCharacteristicValue(characteristic)
} 

fun findClientConfigurationDescriptor(descriptorList: List<BluetoothGattDescriptor>): BluetoothGattDescriptor? {
for (descriptor in descriptorList) {
    if (isClientConfigurationDescriptor(descriptor)) {
        return descriptor
    }
}

return null

}

private fun isClientConfigurationDescriptor(descriptor: BluetoothGattDescriptor?): Boolean {
if (descriptor == null) {
    return false
}
val uuid = descriptor.uuid

if(uuid == CLIENT_CONFIGURATION_DESCRIPTOR) {
    return true
}

return false

val CLIENT_CONFIGURATION_DESCRIPTOR: UUID = UUID.fromString("00002902-0000-1000-8000-00805f9b34fb")

Answer 1

结果是 BLE 服务器出现了问题。 客户端代码完全没有问题。