An open API service indexing awesome lists of open source software.

https://github.com/asyncgui/asynctkinter

Async/await-based framework for Tkinter
https://github.com/asyncgui/asynctkinter

asynchronous tkinter

Last synced: 3 months ago
JSON representation

Async/await-based framework for Tkinter

Awesome Lists containing this project

README

          

# AsyncTkinter

[Youtube](https://youtu.be/8XP1KgRd3jI)

`asynctkinter` 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')`
1. wait for 1sec
1. `print('B')`
1. wait for a label to be pressed
1. `print('C')`

in that order.
Your code would look like this:

```python
def what_you_want_to_do(label):
bind_id = None
print('A')

def one_sec_later(__):
nonlocal bind_id
print('B')
bind_id = label.bind('', on_press, '+')
label.after(1000, one_sec_later)

def on_press(event):
label.unbind('', bind_id)
print('C')

what_you_want_to_do(...)
```

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

```python
import asynctkinter as atk

async def what_you_want_to_do(clock, label):
print('A')
await clock.sleep(1)
print('B')
await atk.event(label, '')
print('C')

atk.start(what_you_want_to_do(...))
```

## Installation

Pin the minor version.

```text
poetry add asynctkinter@~0.4
pip install "asynctkinter>=0.4,<0.5"
```

## Usage

```python
import tkinter as tk
import asynctkinter as atk

async def main(*, clock: atk.Clock, root: tk.Tk):
label = tk.Label(root, text='Hello', font=('', 80))
label.pack()

# waits for 2 seconds to elapse
await clock.sleep(2)

# waits for a label to be pressed
event = await atk.event(label, '')
print(f"pos: {event.x}, {event.y}")

# waits for either 5 seconds to elapse or a label to be pressed.
# i.e. waits at most 5 seconds for a label to be pressed
tasks = await atk.wait_any(
clock.sleep(5),
atk.event(label, ''),
)
if tasks[0].finished:
print("Timeout")
else:
event = tasks[1].result
print(f"The label got pressed. (pos: {event.x}, {event.y})")

# same as the above
async with clock.move_on_after(5) as timeout_tracker:
event = await atk.event(label, '')
print(f"The label got pressed. (pos: {event.x}, {event.y})")
if timeout_tracker.finished:
print("Timeout")

# waits for both 5 seconds to elapse and a label to be pressed.
tasks = await atk.wait_all(
clock.sleep(5),
atk.event(label, ''),
)

# nests as you want.
tasks = await ak.wait_all(
atk.event(label, ''),
atk.wait_any(
clock.sleep(5),
...,
),
)
child_tasks = tasks[1].result

if __name__ == "__main__":
atk.run(main)
```

### threading

Unlike `trio` and `asyncio`, `asynckivy` does not provide any I/O primitives.
Therefore, if you don’t want to implement your own, using threads may be the best way to perform I/O without blocking the main thread.

```python
from concurrent.futures import ThreadPoolExecuter
import asynctkinter as atk

executer = ThreadPoolExecuter()

async def async_fn(clock: atk.Clock):
# create a new thread, run a function inside it, then
# wait for the completion of that thread
r = await atk.run_in_thread(clock, thread_blocking_operation)
print("return value:", r)

# run a function inside a ThreadPoolExecuter, and wait for its completion.
# (ProcessPoolExecuter is not supported)
r = await atk.run_in_executer(clock, executer, thread_blocking_operation)
print("return value:", r)
```

Unhandled exceptions (excluding `BaseException` that is not `Exception`) are propagated to the caller
so you can catch them like you do in synchronous code:

```python
import requests
import asynctkinter as atk

async def async_fn(clock: atk.Clock):
try:
r = await atk.run_in_thread(clock, lambda: requests.get('htt...', timeout=10), ...)
except requests.Timeout:
print("TIMEOUT!")
else:
print('RECEIVED:', r)
```

## Notes

- You may want to read the [asyncgui's documentation](https://asyncgui.github.io/asyncgui/) as it is the foundation of this library.
- You may want to read the [asyncgui_ext.clock's documentation](https://asyncgui.github.io/asyncgui-ext-clock/) as well.
- I, the author of this library, am not even a tkinter user so there may be plenty of weird code in the repository.