Python3使用asyncio的run_forever时如何点击tkinter关闭按钮干净退出应用

• RequestQuit 函数逻辑缺失：当前代码仅在busyProcessing为True时才会设置退出标记，若当前无运行中的异步任务，busyProcessing为默认的False，函数执行后无任何操作，点击关闭按钮不会触发任何退出流程。
• 缺少time模块导入：AfterIdle方法中调用了time.time()，但代码头部未导入time模块，运行到该逻辑时会抛出异常，终止后续退出流程。
• 第三方库兼容问题：aiotkinter已经多年未更新，部分版本与树莓派搭载的Python 3.7环境存在适配问题，无法正确调度tkinter的窗口事件回调。
• （可选环境校验）如果窗口可以正常显示仅关闭按钮无效可忽略此条：SSH X11转发场景下需确认XQuartz开启了「允许来自网络客户端的连接」选项，且ssh连接时添加了-X参数。

最小改动修复（保留aiotkinter依赖） #

补全代码逻辑即可，修改点如下：

1. 头部添加import time导入
2. 补全RequestQuit函数的分支逻辑，无运行中任务时直接设置退出标记

修复后完整代码：

from tkinter import *
from tkinter import messagebox
import aiotkinter
import asyncio
import time # 新增导入

afterIdleProcessingIntervalMsec = 500 # Adjust for UI responsiveness here.
busyProcessing = False
quitRequested = False

def RequestQuit():
  global quitRequested
  global busyProcessing
  if busyProcessing:
    answer = messagebox.askquestion('Exit application', 'Do you really want to abort the ongoing processing?', icon='warning')
    if answer == 'yes':
      quitRequested = True
  else:
    # 新增分支：无运行中任务直接标记退出
    quitRequested = True

def AfterIdle():
  global quitRequested
  global loop
  global root
  if not quitRequested:
    root.after(afterIdleProcessingIntervalMsec, AfterIdle)
  else:
    print("Destroying GUI at: ", time.time())
    try:
      loop.stop()
      root.destroy()
    except:
      exit(0)

if __name__ == '__main__':
  global root
  global loop
  asyncio.set_event_loop_policy(aiotkinter.TkinterEventLoopPolicy())
  loop = asyncio.get_event_loop()
  root = Tk()
  root.protocol("WM_DELETE_WINDOW", RequestQuit)
  root.after_idle(AfterIdle)
  # Create and pack widgets here.
  loop.run_forever()

无第三方依赖修复方案（推荐，兼容性更好） #

放弃已经停止维护的aiotkinter，用原生逻辑整合tkinter和asyncio事件循环，适配所有Python 3.7+环境：

from tkinter import *
from tkinter import messagebox
import asyncio
import time

afterIdleProcessingIntervalMsec = 500
busyProcessing = False
quitRequested = False
loop = asyncio.new_event_loop()
asyncio.set_event_loop(loop)

def RequestQuit():
  global quitRequested
  global busyProcessing
  if busyProcessing:
    answer = messagebox.askquestion('Exit application', 'Do you really want to abort the ongoing processing?', icon='warning')
    if answer == 'yes':
      quitRequested = True
  else:
    quitRequested = True

def AfterIdle():
  global quitRequested
  global root
  if not quitRequested:
    root.after(afterIdleProcessingIntervalMsec, AfterIdle)
  else:
    print("Destroying GUI at: ", time.time())
    try:
      root.destroy()
      loop.stop()
    except:
      exit(0)

# 调度asyncio事件循环
def run_asyncio_loop():
    loop.call_soon(loop.stop)
    loop.run_forever()
    if not quitRequested:
        root.after(10, run_asyncio_loop)

if __name__ == '__main__':
  root = Tk()
  root.protocol("WM_DELETE_WINDOW", RequestQuit)
  root.after_idle(AfterIdle)
  root.after_idle(run_asyncio_loop)
  # Create and pack widgets here.
  root.mainloop()

内容的提问来源于stack exchange，提问作者zenmaster43