Implement an event system

[dalonsoa]

wxPython comes with a built in event system that let's you code your own events and callbacks, and having the application mainloop schedule and execute the callbacks at the appropriate time (see events in the thread system). It is not that intuitive to use, though, and all callbacks are executed in the main thread, which might not be convenient.

An alternative method is suggested that mixes the builtin events system and PyPubSub messaging tool. An implementation using decorators will look like the following:

@event.listen("some.channel", in_thread=False)
def foo(a, b) -> None:
	# Do something
	pass

If in_thread=True, the decorated function will be executed in the same thread than the one broadcasting messages via "some.channel". Otherwise, the event will be connected to the main window of the program and executed with wx.PostEvent. Again, see the handling of the end of a thread in the thread system.

The broadcasting of a message is independent on who will be handling the message or where. A simple event.broadcast function with the same API than pubsub.pub.sendMessage will work. Under the hood, it will send the message to the normal pubsub system - probably "as is" if the API is the same -, but additionally will send an approrpiately crafted signal via the built-in event system to trigger those events that have been configured with in_thread=False.