do you want to test both wrapper ?
for Serial_CAN, wrapper it don't manage events, you have to run "begin" first and to make a loop waiting for data like in Arduino.
for MCP_CAN, after a modification on original cpp file, i was able to compile example project in Arduino and i was able to make a wrapper with event management
i cannot test both because i don't have hardware but compilation and B4X interface seems OK
good luck!