RuntimeError：メインスレッドはメインループにはありません。終了ボタンをクリックしたとき

Question

私は、特定のイベントからの時間をカウントする簡単なGUIアプリケーションを構築しています。とにかく、すべてが正常に動作しますが、私は[終了]ボタンをクリックしたとき、それは例外に私にこのような毎秒与えることを開始します。ここでは

Exception in thread Thread-10: Traceback (most recent call last): File "/usr/lib/python3.5/threading.py", line 914, in _bootstrap_inner 
    self.run() File "/usr/lib/python3.5/threading.py", line 1180, in run 
    self.function(*self.args, **self.kwargs) File "/home/cali/PycharmProjects/str8/str8", line 83, in printit 
    display() File "/home/cali/PycharmProjects/str8/str8", line 23, in display 
    font="Verdana 8 bold").grid(row=0, sticky=W) File "/usr/lib/python3.5/tkinter/__init__.py", line 2609, in __init__ 
    Widget.__init__(self, master, 'label', cnf, kw) File "/usr/lib/python3.5/tkinter/__init__.py", line 2142, in __init__ 
    (widgetName, self._w) + extra + self._options(cnf)) RuntimeError: main thread is not in main loop 

することは、私がやっていることです：私が使用している

# str8.py 
# Program to count time from a certain event 

from tkinter import * 
from datetime import * 
from threading import * 

root = Tk() 
root.title("STR8") 
root.resizable(width=False, height=False) 

def main(): 
    printit() 

def exit(): 
    root.destroy() 

def display(): 
    event, tday, str8, seconds, minutes, hours, days, weeks, years = calculate() 

    thelabel = Label(root, 
         text="You have been STR8 for:\n", 
         font="Verdana 8 bold").grid(row=0, sticky=W) 

    labelYears = Label(root, 
          text="Years: " 
           + str(round(years, 2)), 
          font="Verdana 8").grid(row=1, sticky=W) 

    labelWeeks = Label(root, 
          text="Weeks: " 
           + str(round(weeks, 2)), 
          font="Verdana 8").grid(row=2, sticky=W) 

    labelDays = Label(root, 
          text="Days: " 
           + str(round(days, 2)), 
          font="Verdana 8").grid(row=3, sticky=W) 

    labelHours = Label(root, 
          text="Hours: " 
           + str(round(hours, 2)), 
          font="Verdana 8").grid(row=4, sticky=W) 

    labelMinutes = Label(root, 
          text="Minutes: " 
            + str(round(minutes, 2)), 
          font="Verdana 8").grid(row=5, sticky=W) 

    labelSeconds = Label(root, 
          text="Seconds: " 
            + str(round(str8.total_seconds())), 
          font="Verdana 8").grid(row=6, sticky=W) 

    buttonRefresh = Button(root, 
           text="EXIT", 
           font="Verdana 8", 
           height=1, 
           width=19, 
           command=exit).grid(row=7) 


def calculate(): 
    event = datetime(2017, 3, 29, 13, 45, 0) 
    tday = datetime.now() 

    str8 = tday - event 

    seconds = str8.total_seconds() 
    minutes = str8.total_seconds()/60 
    hours = minutes/60 
    days = hours/24 
    weeks = days/7 
    years = weeks/52 

    return event, tday, str8, seconds, minutes, hours, days, weeks, years 



def printit(): 
    Timer(1.0, printit).start() 
    calculate() 
    display() 


main() 
root.mainloop() 

Python 3.6。

Answer 1

問題を解決するために、次のプログラムが表示されます。 の電話番号はprint_itで、tryブロックにラップされています。例外なく成功した場合は、後でタイマーの実行を開始します。

# str8.py 
# Program to count time from a certain event 

from tkinter import * 
from datetime import * 
from threading import * 

root = Tk() 
root.title("STR8") 
root.resizable(width=False, height=False) 


def main(): 
    print_it() 


def stop(): 
    root.destroy() 


def display(): 
    event, today, str8, seconds, minutes, hours, days, weeks, years = calc() 
    Label(root, 
      text="You have been STR8 for:\n", 
      font="Verdana 8 bold").grid(row=0, sticky=W) 
    Label(root, 
      text="Years: " 
       + str(round(years, 2)), 
      font="Verdana 8").grid(row=1, sticky=W) 
    Label(root, 
      text="Weeks: " 
       + str(round(weeks, 2)), 
      font="Verdana 8").grid(row=2, sticky=W) 
    Label(root, 
      text="Days: " 
       + str(round(days, 2)), 
      font="Verdana 8").grid(row=3, sticky=W) 
    Label(root, 
      text="Hours: " 
       + str(round(hours, 2)), 
      font="Verdana 8").grid(row=4, sticky=W) 
    Label(root, 
      text="Minutes: " 
       + str(round(minutes, 2)), 
      font="Verdana 8").grid(row=5, sticky=W) 
    Label(root, 
      text="Seconds: " 
       + str(round(str8.total_seconds())), 
      font="Verdana 8").grid(row=6, sticky=W) 
    Button(root, 
      text="EXIT", 
      font="Verdana 8", 
      height=1, 
      width=19, 
      command=stop).grid(row=7) 


def calc(): 
    event = datetime(2017, 3, 29, 13, 45, 0) 
    today = datetime.now() 

    str8 = today - event 

    seconds = str8.total_seconds() 
    minutes = str8.total_seconds()/60 
    hours = minutes/60 
    days = hours/24 
    weeks = days/7 
    years = weeks/52 

    return event, today, str8, seconds, minutes, hours, days, weeks, years 


def print_it(): 
    t = Timer(1.0, print_it) 
    calc() 
    try: 
     display() 
    except RuntimeError: 
     pass 
    else: 
     t.start() 


main() 
root.mainloop()