tkinter 窗口没有响应

Question

我有一个 GUI 可以做一些事情，然后重新启动面板，然后等待面板完成重新启动。这个想法是让用户按下“PROGRAM HMI”，它将执行动作（）。我最大的问题是在重启过程中，GUI 需要等待 10 秒才能让 HMI 重启。在这 10 秒内，GUI 冻结，顶部出现“窗口无响应”消息。正如我在终端中看到的那样，代码正在执行，它的 GUI 最终解冻。我读过我不应该在这里使用 time.sleep() 。但是我应该怎么写它才不会冻结？我正在使用 python 3.8。

import requests
import json
import time
import warnings
import subprocess
import xml.etree.ElementTree as ET
from ftplib import FTP
import hashlib
from datetime import datetime
import sys
import tkinter as tk
import time
import threading
from tkinter import *

class main:
    def __init__(self):
        self.window = tk.Tk()
        self.window.title("1750+ HMI Setup App")
        self.window.geometry("550x675")
        self.window.resizable(width=False, height=False)
        self.window.configure(bg='#34aeeb')

        self.action_updateIP = False

        self.ipString = "192.168.0.20"    # Should be found by DHCP server.
        self.newIPString = "192.168.0.20" # Default.
        self.url = "https://" + self.ipString + "/"   # TODO: Get IP address based on DHCP of panel, or fixed 192.168.0.1 if it exists?
        self.urlConfig = self.url + "machine_config/"
        self.urlApi = self.url + "rest/api/v1/"
        self.authData = ('admin', 'admin')
        
        #OUTPUT TEXT BOX
        self.outText = Text(self.window, width=50, height=20, wrap=WORD)
        self.outText.grid(row=10, columnspan=3, padx=10)

        self.make_widgets()
        self.window.mainloop()

    def make_widgets(self):
        Button(self.window, text='Select All', font=("Arial", 12), width=10, command=self.select_all).grid(row=7, sticky=W, padx=10, pady=20)

        ButtonShow = tk.Button(text="Program HMI", width=20, font=("Arial", 14), command=self.actions)
        ButtonShow.grid(column=0, row=8, sticky=W, padx=10, pady=10)

    def verboseSleep(self,seconds):
        chars = len(str(seconds))
        s = "{:" + str(chars) + "d}s"
        cntdn = seconds + 1
        for i in range(seconds, 0, -1):
            sys.stdout.write(str("\b" * (chars+1)) + s.format(i))
            cntdn = cntdn - 1    
            msg_seconds = str(cntdn)
            self.outText.insert(tk.END, str(cntdn))
            pos = self.outText.index('end')
            float_pos = float(pos) - 1.0
            self.window.update_idletasks()
            sys.stdout.flush()
            self.window.after(1000)
            self.outText.delete(str(float_pos), "end")
            self.outText.insert(tk.END, "\n")     

        sys.stdout.write(str("\b" * (chars + 1)))   # Remove all evidence of our countdown timer.
        sys.stdout.flush()

    def select_all(self):
        self.action_updateIP = True

    def actions(self):
        ##########################################################    
        ipString = "192.168.0.20"    # Should be found by DHCP server.
        newIPString = "192.168.0.20" # Default.
        self.outText.delete(1.0, END)
        #print (self.action_updateIP)
        if self.action_updateIP == True:
            print("Updating IP address...")
            self.outText.insert(tk.END, "Updating IP address...")  
            self.window.update_idletasks()
            postData = {"bridge":{"enabled":False,"interfaces":["eth0"],"list":[]},"wifi":{"interfaces":[]},"version":0,"dns":{"servers":[],"search":[]},"hostname":"HMI-2133","interfaces":[{"name":"eth0","label":"WAN","mac_address":"00:30:d8:06:21:33","dhcp":False,"configured":True,"readonly":False,"virtual":False,"hidden":False,"actual_netmask":"255.255.255.0","actual_ip_address":ipString,"ip_address":newIPString,"netmask":"255.255.255.0","gateway_ip":"192.168.0.100"},{"name":"lo","mac_address":"00:00:00:00:00:00","dhcp":False,"configured":True,"readonly":True,"virtual":True,"hidden":True,"actual_netmask":"255.0.0.0","actual_ip_address":"127.0.0.1"}]}
            try:
            # We expect this to fail due to the connection being abruptly ended by the panel...
                r = requests.post(url = urlApi + 'network', data = json.dumps(postData), timeout = 10, headers={"content-type": "application/json"}, auth=authData, verify=False)
            except:
                print("Waiting 10s for panel to update.")
                self.outText.insert(tk.END, "Waiting 10s for panel to update" + "\n")  
                self.window.update_idletasks()
                self.verboseSleep(10)

            print("IP Updated.  New IP: ", newIPString)
            msg_newIP = "IP Updated. New IP: " + newIPString + "\n"
            self.outText.insert(tk.END, msg_newIP)  
            self.window.update_idletasks()       
            self.ipString = self.newIPString
        else:
            print (self.action_updateIP)
            print ('Done!' + "\n")
            self.outText.insert(tk.END, "Done! DONE! I'm all DONE!!" +"\n")

main()
exit(0)

Answer 1

查看 tkinter 中的 after 方法。您基本上可以设置延迟执行任务的时间，而不会冻结 UI

类似

window = tk.Tk()

...

def do_actions():
   some_function_calls

...

# delay is given in milliseconds, so you need to multiply with 1000 to get in seconds
window.after(10000, do_actions)  

如果您希望将其创建为循环，则可以执行以下操作：

def do_actions():
    some_function_calls
    return window.after(10000, do_actions)

after_loop = do_actions()

那么如果你想取消after循环，可以调用window.after_cancel(after_loop)

Answer 2

使用线程模块在python中使用多线程可以避免“无响应”问题。

如果你定义了任何函数，比如 combine() 被添加为按钮中的命令：

btn = Button(root, text="Click Me",command=combine)

由于窗口冻结，则编辑上述类型代码如下图：

import threading
btn = Button(root,text="Click Me", command=threading.Thread(target=combine).start()) 

看看参考：stackoverflow - avoid freezing of tkinter window using one line multithreading code