appearance property
Appearance is the way the device should show up in the user interface.
For example if it should show up as a phone 0x0040
to 0x007For as a speaker
0x0841`. The full list of appearance values can be found
in the Bluetooth specifications found here:
https://specificationrefs.bluetooth.com/assigned-values/Appearance%20Values.pdf
The value is technically an unsigned short (uint16), but dart2js doesn't have that type so it is an int here.
Implementation
@override
final int? appearance;