Issue with Bluetooth LE service discovery - QLowEnergyService::UnknownError

akshaybabloo

On Windows 10 (works fine on macOS), I have been getting QLowEnergyService::UnknownError whenever I try to rerun the application but works fine when I try to run it after a while (say 15 mins). Whenever I get the UnknownError, the QLowEnergyService::stateChanged is stuck on QLowEnergyService::DiscoveryRequired.

I tried queuing QLowEnergyController::serviceDiscovered, as mentioned in https://forum.qt.io/topic/117241/why-qlowenergyservice-unknownerror, but that didn't help.

Not sure what's happening here - any help is appreciated

akshaybabloo

Looks like this is a known issue https://bugreports.qt.io/browse/QTBUG-80770 and https://bugreports.qt.io/browse/QTBUG-78488.

A workaround is to add:

 QTimer::singleShot(0, [=]() {
     service->discoverDetails();
 });