AsyncKivy

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asynckivy is an async library that saves you from ugly callback-style code, like most of async libraries do. Let's say you want to do:

1. print('A')
2. wait for 1sec
3. print('B')
4. wait for a button to be pressed
5. print('C')

in that order. Your code would look like this:

from kivy.clock import Clock

def what_you_want_to_do(button):
    print('A')

    def one_sec_later(__):
        print('B')
        button.bind(on_press=on_button_press)
    Clock.schedule_once(one_sec_later, 1)

    def on_button_press(button):
        button.unbind(on_press=on_button_press)
        print('C')

what_you_want_to_do(...)

It's not easy to understand. If you use asynckivy, the code above will become:

import asynckivy as ak

async def what_you_want_to_do(button):
    print('A')
    await ak.sleep(1)
    print('B')
    await ak.event(button, 'on_press')
    print('C')

ak.managed_start(what_you_want_to_do(...))

Installation

Pin the minor version.

poetry add asynckivy@~0.9
pip install "asynckivy>=0.9,<0.10"

Usage

import asynckivy as ak

async def some_task(button):
    # waits for 2 seconds to elapse
    dt = await ak.sleep(2)
    print(f'{dt} seconds have elapsed')

    # waits for a button to be pressed
    await ak.event(button, 'on_press')

    # waits for the value of 'button.x' to change
    __, x = await ak.event(button, 'x')
    print(f'button.x is now {x}')

    # waits for the value of 'button.x' to become greater than 100
    if button.x <= 100:
        __, x = await ak.event(button, 'x', filter=lambda __, x: x>100)
        print(f'button.x is now {x}')

    # waits for either 5 seconds to elapse or a button to be pressed.
    # i.e. waits at most 5 seconds for a button to be pressed
    tasks = await ak.wait_any(
        ak.sleep(5),
        ak.event(button, 'on_press'),
    )
    print("Timeout" if tasks[0].finished else "The button was pressed")

    # same as the above
    async with ak.move_on_after(5) as bg_task:
        await ak.event(button, 'on_press')
    print("Timeout" if bg_task.finished else "The button was pressed")

    # waits for both 5 seconds to elapse and a button to be pressed.
    tasks = await ak.wait_all(
        ak.sleep(5),
        ak.event(button, 'on_press'),
    )

    # nest as you want.
    # waits for a button to be pressed, and either 5 seconds to elapse or 'other_async_func' to complete.
    tasks = await ak.wait_all(
        ak.event(button, 'on_press'),
        ak.wait_any(
            ak.sleep(5),
            other_async_func(),
        ),
    )
    child_tasks = tasks[1].result
    print("5 seconds elapsed" if child_tasks[0].finished else "other_async_func has completed")

ak.managed_start(some_task(some_button))

For more details, read the documentation.

Tested on

• CPython 3.10 + Kivy 2.3
• CPython 3.11 + Kivy 2.3
• CPython 3.12 + Kivy 2.3
• CPython 3.13 + Kivy 2.3