Device was Disconnected - monitorCharacteristicForService

Prerequisites

• I am running the latest version
• I checked the documentation and found no answer
• I checked to make sure that this issue has not already been filed

Expected Behavior

Monitoring a characteristic for notifications, should receive the notifications.

Current Behavior

Receive an error that is not very detailed, I tried adding logs to the java code, to see what happens and where. This is as far as I’ve come:

In BleModule.java, the function “safeMonitorCharacteristicForDevice”, the setupMode is set to “QUICK_SETUP”, and it setup a notification (

if ((properties & BluetoothGattCharacteristic.PROPERTY_NOTIFY) != 0) {
                    Log.e("BleModule", "[safeMonitorCharacteristicForDevice] setupNotification");
                    return connection.setupNotification(gattCharacteristic, setupMode);
}

And the error function gets invoked:

@Override
public void onError(Throwable e) {
                        Log.e("BleModule", "[safeMonitorCharacteristicForDevice] onError error toString: " + e.toString());
                        Log.e("BleModule", "[safeMonitorCharacteristicForDevice] onError error message: " + e.getMessage());
                        errorConverter.toError(e).reject(promise);
                        transactions.removeSubscription(transactionId);
}

The Log.e produce the following:

E/BleModule: [safeMonitorCharacteristicForDevice] setup mode: Quick Setup
E/BleModule: [safeMonitorCharacteristicForDevice] setupNotification
E/BleModule: [safeMonitorCharacteristicForDevice] onError error toString: com.polidea.rxandroidble.exceptions.BleDisconnectedException: Disconnected from .... with status 0 (GATT_SUCCESS)
E/BleModule: [safeMonitorCharacteristicForDevice] onError error message: Disconnected from .... with status 0 (GATT_SUCCESS)

Where “…” is a unique device ID.

Steps to Reproduce

Please provide detailed steps for reproducing the issue.

1. writeCharacteristicWithoutResponseForService for the RECORD_ACCESS_CONTROL_POINT, with the byte values [1, 1], encoded in Base64 format.
2. monitorCharacteristicForService for the Glucose Measurement (00002A18) and Glucose Measurement Context (00002A34) characteristic.
3. Experience the error.

Context

• Library version: “react-native-ble-plx”: “^1.0.3”
• Platform: Android

[tymoxx]

@harguus I put setInterval inside the connect() function. Here is a simplified code. Your code will be different depending on how you connect to your device:

async connect(id) {
            const device = await deviceManager.connectToDevice(id);
            const discoveredDevice = await device.discoverAllServicesAndCharacteristics();

            /* Sync periodically - to keep device connected*/
            const interval = setInterval(function () {
                const value = 'your_value'; // in my case, I synchronize time between the app and device. But you can do anything - it's just to keep the device connected.
                discoveredDevice.writeCharacteristicWithResponseForService(SERVICE_UUID, WRITE_CHARACTERISTIC_UUID, value);
            }, 40000);
            dispatch(saveInterval(interval)); // I also save the instance of the interval to the state, so I can do clearInterval later.
}

[tymoxx]

@joaovitorqueiroz In my case, the device was disconnecting after 45 seconds. So I added setInterval to do writeCharacteristicWithoutResponseForService every 40 seconds(which just gets the status of the device). And it keeps the device connected.