Retrieving descriptors and properties from characteristics

Hello,

I’m trying to port a library for Android (provided by the manufacturer of my device) from Java to JS using react-native-ble-plx.

Specifically, I’m having trouble understanding how to enable notifications, retrieve descriptors and properties of a characteristic:

BluetoothGattService service = gatt.getService(AndroidBluetoothConnection.METER_UUID);
mBluetoothGattChar = service.getCharacteristic(AndroidBluetoothConnection.METER_UUID2);
mDescriptor = ((BluetoothGattDescriptor)mBluetoothGattChar.getDescriptors().get(0));
mCharaProp = mBluetoothGattChar.getProperties();
          
AndroidBluetoothConnection.this.setCharacteristicNotification(mBluetoothGattChar, true);

Interestingly, the characteristic discovered has “isNotifying” set to “false”, even though the original code is enabling notification for the same characteristic. My code so far:

d.characteristicsForService('00001523-1212-efde-1523-785feabcd123').then((s) => {
    s.forEach((c) => {
        if (c.uuid === '00001524-1212-efde-1523-785feabcd123') {
            console.warn(c);
            const characteristic = d.writeCharacteristicWithResponseForService(
                c.serviceUUID,
                c.uuid,
                "AQ==" /* 0x01 in hex */
            ).then((characteristic) => {
                console.warn(characteristic);

                d.monitorCharacteristicForService(c.serviceUUID, c.uuid, (error, characteristic) => {
                /* Never reached */
                if (error) {
                    console.warn(error.message)
                    return;
                }
                console.warn('notified');
                console.warn(characteristic.uuid);
                console.warn(characteristic.value.toString());
            })
    })
    .catch((e) => {
        console.warn(e);
    })
});

Here is the library code for reference: https://gist.github.com/patrick-samy/4af06b06441e83fc9adb6b81db30ef3c

[Cierpliwy]

@nixoschu This is something, which is missing in the library and definitely should be implemented. I’ll schedule work to fully support descriptors.

[SuvabBaral]

Hi @Cierpliwy , the peripheral device I am using supports indicate, however, after the first command, my app(central device) is disabling the indication and all the subsequent commands are sent as notify. Is there a way I can continue sending commands as indicate rather than notify using the react-native-ble-plx in both android and iOS?.

I have added the same question on stackoverflow: https://stackoverflow.com/questions/66868468/react-native-ble-plx-is-it-possible-for-configuring-indicate-as-a-standard-prot