About the handler options’ type¶
This page explains the event handler options argument’s type.
The dictionary type is acceptable¶
Each handler’s options argument can accept a dictionary type value, like the following:
from typing import Dict
import apysc as ap
def on_timer(e: ap.TimerEvent, options: Dict[str, str]) -> None:
"""
The handler that a timer calls.
Parameters
----------
e : ap.TimerEvent
Event instance.
options : dict
Optional arguments dictionary.
"""
ap.trace(options["msg"])
timer: ap.Timer = ap.Timer(on_timer, delay=1000, options={"msg": "Hello!"})
timer.start()
About the TypedDict annotation¶
Sometimes using the TypedDict type annotation instead of the dict type annotation is helpful and makes it easy to read the code. The apysc check a handler options annotation and the actual options value type when you use the TypedDict.
from typing_extensions import TypedDict
import apysc as ap
class _MsgOptions(TypedDict):
msg: str
def on_timer(e: ap.TimerEvent, options: _MsgOptions) -> None:
"""
The handler that a timer calls.
Parameters
----------
e : ap.TimerEvent
Event instance.
options : dict
Optional arguments dictionary.
"""
ap.trace(options["msg"])
options: _MsgOptions = {"msg": "Hello!"}
timer: ap.Timer = ap.Timer(on_timer, delay=1000, options=options)
timer.start()
Notes: if you are using a Python 3.8 or later version, then importing the TypedDict from the typing package instead of the typing_extensions is available (e.g., from typing import TypedDict).
