How to use `vm.register_on_button`?

[BlockOG]

I have found that it needs to do this: vm.register_on_button(some_constant_idk, handler, "left" or "right", "pressed" or "released") but I don't really understand what handler has to return, it has to return a list of integers, but what integers Idk

[PeterStaev]

Hey @BlockOG , thanks for your research! From what I tried there is no need the handler to return anything. For example linked a handler with a print command and it worked fined. Added a section in the advanced features doc.

[BlockOG]

When I tried that I got a NoneType is not iterable error I also did a print in the handler function and I only saw that print after the program ended, so Idk

[PeterStaev]

It is working fine when I tried it on my end.

[BlockOG]

@PeterStaev Could you maybe give me a program that I can test on my spike prime to see if it works? (a program which uses vm.register_on_button)

[PeterStaev]

@BlockOG this is what i did on my end:

# LEGO type:advanced slot:19 autostart
from runtime.virtualmachine import VirtualMachine

async def on_start(vm, stack):
    print("This is the spot of your code")

async def on_press(vm, stack):
    print("Button pressed")

def setup(rpc, system, stop):
    vm = VirtualMachine(rpc, system, stop, "something_unique")
    vm.register_on_start("another_unique_string", on_start)
    vm.register_on_button("another_unique_string1", on_press, "left", "pressed")
    return vm

[BlockOG]

I got it working in the end, problem was that I had a while true loop in on_start since I was creating games