requestLEScan(): do we have control over how the devices list is displayed?

[bonatoc]

Hello,

First of all thank you for this well-made library.
We're about to publish a free app (iOS and Android) built upon it (Quasar 2 with Capacitor).

I was wondering if it was possible to alter/modify the scan result that appears in the OS pop-up.

The app scans the devices using requestLEScan() with services, which contains the manufacturer's service ID, and all is well.

In iOS,
the pop-up lists (correctly) the devices by their name:

In Android,
the devices list in the popup looks like this (below are the exact same devices listed in the iOS pop-up above):

It looks like iOS and Android are not looking for the same Generic Access (0x1800) characteristic.
iOS returns the value of Generic Access 0x2A00,
whereas Android returns the value of Generic Access 0x2A01 (hence the "Unknown" string returned)

Here's two NRF Connect screenshots:

Do we have any control over what's displayed in the Android "scan result" pop-up?
At the very least we would like to get rid of the MAC address of the device.

Thank you.

[peitschie]

Hi @bonatoc

To eliminate the "Unknown" display in this list, you need to look at adding a localName value to the advertising packet from the peripheral.

The 0x1800 service you are showing above is only available after connection, so would not impact the display in this list, which can only use data in the advertising payloads. I suspect that the peripheral firmware is correctly setting the GAP name (which iOS will use), and not specifying an advertised local name, which Android uses.

You can confirm this by looking at the advertising payloads in nrf Connect. You can see in this screenshot here that there is a Complete Local Name field: https://play-lh.googleusercontent.com/yWNXh7QqlKDkbRDQyQjHqRI6_dc50Ww2GplGKVYdjZy7AFooMMeeMSJaHMXoiJ8aC3c=w2560-h1440

If you want further customisation of the display dialog (e.g., to remove the MAC address), you may want to consider implementing your own list using requestLEScan and Quasar.

[bonatoc]

Hi @peitschie ,

Thank you for you quick answer.

It seems that localName is provided in the advertising packet, see screencap (Android NRF Connect):

So I think in the meantime I'm going to focus on the customisation of the display dialog.
Did you mean by that, I can completely bypass the native OS popup and implement my own?

Can you please point me to which files/functions have to be modified?
Is it the function itself, in plugin.cjs.js (@capacitor-community/bluetooth-le/dist)?
...or is rather in BluetoothLe.kt ?

Thank you!

[peitschie]

Did you mean by that, I can completely bypass the native OS popup and implement my own?

Exactly this. requestLEScan takes a callback, that you can wire into your javascript UI toolkit of choice. In this case, I presume you'd feed this into a Quasar dialog of some description. There should be no need to modify anything within this plugin itself, as you are going to be writing in your web tech, not native code.