运行时错误：主线程不在调用Tkin的Flask的主循环中

Question

我正在安装一个Facebook messenger机器人，它可以在我的笔记本电脑上远程执行代码（即截图、显示消息）。当我从messenger发送消息“msg hello”时，bot将使用Tkinter显示一个带有“hello”的消息框。你知道吗

程序返回错误：

RuntimeError: main thread is not in main loop

我试着用：

root = tkinter.Tk()
root.mainloop()

但是程序只是停留在那里（就像一个while True循环）

以下是我的主烧瓶应用程序的代码：

from flask import Flask, request 
from pymessenger.bot import Bot

from functions.message_box import msg_box

app = Flask(__name__)
ACCESS_TOKEN = 'my token' # I removed these tokens on purpose
VERIFY_TOKEN = 'my token'
bot = Bot(ACCESS_TOKEN)

@app.route("/", methods=['GET', 'POST'])
def receive_message():
    if request.method == 'GET':
        # Assuming the request is from facebook's verfication 
        token_sent = request.args.get("hub.verify_token")
        return verify_fb_token(token_sent)
    else:
        # get whatever message a user sent the bot
       output = request.get_json()
       for event in output['entry']:
          messaging = event['messaging']
          for message in messaging:
            if message.get('message'):
                #Facebook Messenger ID for user so we know where to send response back to
                recipient_id = message['sender']['id']
                # get code from the message
                text = message['message'].get('text')
                code = text[:text.find(' ')]     # find the first word in the message
                if code == 'msg':
                    msg = text[text.find(' ') + 1:]     # get the message except the code
                    msg_box(msg)
                    send_message(recipient_id, f'Sent: {msg}')

    return "Message Processed"

def verify_fb_token(token_sent):
    if token_sent == VERIFY_TOKEN:
        return request.args.get("hub.challenge")
    return 'Invalid verification token'

#uses PyMessenger to send response to user
def send_message(recipient_id, response):
    #sends user the text message provided via input response parameter
    bot.send_text_message(recipient_id, response)
    return "success"

if __name__ == "__main__":
    app.run()

这是我的信息代码_方框.py（要在窗口上显示消息框）：

'''
    Purpose: Display msg box on screen
'''
import tkinter
from tkinter import messagebox

# hide main window
root = tkinter.Tk()
# root.mainloop()
root.withdraw()

def msg_box(msg):
    messagebox.showinfo("Information", msg)
    return 1

我收到的完整错误：

 * Serving Flask app "app" (lazy loading)
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
   Use a production WSGI server instead.
 * Debug mode: off
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
[2019-09-05 15:52:47,663] ERROR in app: Exception on / [POST]
Traceback (most recent call last):
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 2446, in wsgi_app
    response = self.full_dispatch_request()
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1951, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1820, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\_compat.py", line 39, in reraise
    raise value
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1949, in full_dispatch_request
    rv = self.dispatch_request()
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1935, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "app.py", line 59, in receive_message
    msg_box(msg)
  File "C:\Users\kevin\Desktop\python\laptopRemoteController\functions\message_box.py", line 13, in msg_box
    messagebox.showinfo("Information", msg)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\messagebox.py", line 83, in showinfo
    return _show(title, message, INFO, OK, **options)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\messagebox.py", line 72, in _show
    res = Message(**options).show()
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\commondialog.py", line 39, in show
    w = Frame(self.master)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 2744, in __init__
    Widget.__init__(self, master, 'frame', cnf, {}, extra)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 2299, in __init__
    (widgetName, self._w) + extra + self._options(cnf))
RuntimeError: main thread is not in main loop
127.0.0.1 - - [05/Sep/2019 15:52:47] "POST / HTTP/1.1" 500 -
[2019-09-05 15:52:49,220] ERROR in app: Exception on / [POST]
Traceback (most recent call last):
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 2446, in wsgi_app
    response = self.full_dispatch_request()
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1951, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\app.py", line 1820, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "C:\Users\kevin\AppData\Local\Programs\Python\Python37-32\lib\site-packages\flask\_compat.py", line 39, in reraise

如果有错误，请帮我改正。此外，如果有其他方法，请告诉我如何。你知道吗

谢谢你的时间和耐心。你知道吗