java - Android BLE onCharacteristicChanged 未触发

Question

我有一个医疗设备(名为 SnoreCoach)，我创建了一个 Android 应用程序并与该设备进行低功耗蓝牙连接。一切(连接到设备、将数据写入特征等)都工作正常，除了 OnCharacteristicChanged 没有被触发。

以下是我的BluetoothGattCallback:

private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        super.onConnectionStateChange(gatt, status, newState);
        if (newState == BluetoothProfile.STATE_CONNECTED) {
            broadcastUpdate(ACTION_GATT_CONNECTED);
        } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
            broadcastUpdate(ACTION_GATT_DISCONNECTED);
        }

    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        super.onServicesDiscovered(gatt, status);
        if (status == BluetoothGatt.GATT_SUCCESS) {
            Log.d(TAG, "onServicesDiscovered - success");
            broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
        }
    }

 @Override
    public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
        super.onCharacteristicRead(gatt, characteristic, status);
        if (status == BluetoothGatt.GATT_SUCCESS) {
            Log.d(TAG, "onCharacteristicRead - success");
            broadcastUpdate(ACTION_DATA_AVAILABLE);
        }
    }

    @Override
    public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
        super.onCharacteristicWrite(gatt, characteristic, status);
        if (status == BluetoothGatt.GATT_SUCCESS) {
            Log.d(TAG, "onCharacteristicWrite - success");
            if (writeType.equals("unPair")) {
                mBluetoothGatt.close();
                mBluetoothGatt = null;
                currentlyConnectedPeripheral = null;
            }
        }
    }

    @Override
    public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
        super.onCharacteristicChanged(gatt, characteristic);
        Log.d(TAG, "onCharacteristicChanged");
        broadcastUpdate(ACTION_DATA_AVAILABLE);
    }

    @Override
    public void onReliableWriteCompleted(BluetoothGatt gatt, int status) {
        super.onReliableWriteCompleted(gatt, status);
        Log.d(TAG, "onReliableWriteCompleted");
    }

    @Override
    public void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status) {
        super.onReadRemoteRssi(gatt, rssi, status);
        Log.d(TAG, "onReadRemoteRssi");
    }

    @Override
    public void onMtuChanged(BluetoothGatt gatt, int mtu, int status) {
        super.onMtuChanged(gatt, mtu, status);
        Log.d(TAG, "onMtuChanged");
    }
};

以下是从上面的BluetoothGattCallback调用的“broadcastUpdate”函数:

private void broadcastUpdate(final String action) {
    final Intent intent = new Intent(action);
    sendBroadcast(intent);
}

在我的通话 Activity (SettingsActivity)中，我有以下广播接收器:

private final BroadcastReceiver mGattUpdateReceiver = new BroadcastReceiver() {

    @Override
    public void onReceive(Context context, Intent intent) {
        final String action = intent.getAction();
        switch (action) {
            case BLEService.ACTION_GATT_CONNECTED:
                displayToast("Connected");
                Log.d(TAG, "Connected");
                mBleService.discoverServices();
                break;
            case BLEService.ACTION_GATT_DISCONNECTED:
                displayToast("Disconnected");
                break;
            case BLEService.ACTION_GATT_SERVICES_DISCOVERED:
                Log.d(TAG, "Services Discovered");
                displayToast("Services Discovered");
                mBleService.enableNotification();
                break;
            case BLEService.ACTION_DATA_AVAILABLE:
                displayToast("Data Received");
                break;
        }
    }
};

下面是我的“enableNotification”函数:

 public void enableNotification() {
    BluetoothGattService snorecoachService = mBluetoothGatt.getService(SNORECOACH_SERVICE_UUID);
    if (snorecoachService == null) {
        Log.d(TAG, "snorecoach Service not found!");
        return;
    }

    BluetoothGattCharacteristic bodyMovementChar = snorecoachService.getCharacteristic(BODY_MOVEMENT_UUID);
    if (bodyMovementChar == null) {
        Log.d(TAG, "charateristic not found!");
        return;
    }

    mBluetoothGatt.setCharacteristicNotification(bodyMovementChar, true);

    BluetoothGattDescriptor desc = bodyMovementChar.getDescriptor(CLIENT_CHARACTERISTIC_CONFIG_UUID);
    desc.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE);
    mBluetoothGatt.writeDescriptor(desc);
}

以下是流程:

1)连接时，我将广播作为“已连接”发送到 mGattUpdateReceive，然后在这里开始服务发现。

2)OnServiceDiscovery，我将广播作为“Services Discovered”发送到mGattUpdateReceive，这里我调用“enable notofication”函数来设置“setCharacteristicNotification”，它也会写入所需的描述符。

我已经尝试了从其他 stackOverflow 问题中找到的所有可能选项，但我不知道我做错了什么，导致 onCharacteristic 事件没有被触发。

我花了 2 天多的时间来解决这个问题，但没有成功，因此我们将不胜感激。

Answer 1

如果您想要的是通知而不是指示，请尝试更改

desc.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE);

至

desc.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);