after() 挂起输出窗口

Question

我正在尝试构建一个实时项目，其中状态每秒更新一次，因此某些部分代码会不断重复。当我想更改必须更新的信息时，我只需单击新按钮，它会为我提供第一个窗口，我可以在其中更新新信息。但这样做会给我以下错误。如果我使用 after() 而不是线程，则错误不会出现，但输出窗口会挂起。请帮助我解决这个问题。谢谢。

Exception in thread Thread-2:
    Traceback (most recent call last):
      File "C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python37_64\lib\threading.py", line 926, in _bootstrap_inner
        self.run()
      File "C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python37_64\lib\threading.py", line 1177, in run
        self.function(*self.args, **self.kwargs)
      File "C:/Users/Desktop/Tool/t.py", line 47, in ae
        self.treeview.insert('', 'end',image=self._img, value=(a))
      File "C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python37_64\lib\tkinter\ttk.py", line 1370, in insert
        res = self.tk.call(self._w, "insert", parent, index, *opts)
    _tkinter.TclError: invalid command name ".!treeview"

我有问题的代码：

def aaa(self):
                num_threads = 5 * multiprocessing.cpu_count()
                p = multiprocessing.dummy.Pool(num_threads)
                p.map(self.ping_func, [x for x in Demo2.t1])
                self.process_incoming() 
                #threading.Timer(1.0, self.aaa).start()-this gives the error while pressing new button and updating information
                self.master.after(100, self.aaa) #it hangs the output window 

示例代码：

import multiprocessing.dummy
import multiprocessing
import os
import socket
import sys
import subprocess
import re
import time
import threading
import tkinter.messagebox
from tkinter import ttk
import queue
from tkinter import *

class Demo1:  #window 1
    data=[]
    def __init__(self, master):
        self.master = master
        self.t=tkinter.Text(self.master,height=20,width=50)
        self.t.grid(row=1, column=1)
        self.button = tkinter.Button(self.master,height=3,width=10, text="OK", command = self.new_window)
        self.button.grid(row=2,column=1)

    def new_window(self):
        self.inputValue=self.t.get("1.0",'end-1c')
        Demo1.data=self.inputValue.split("\n")
        self.master.destroy() # close the current window
        self.master = tkinter.Tk() # create another Tk instance
        self.app = Demo2(self.master) # create Demo2 window
        self.master.mainloop()

class Demo2: #window 2
    value = []
    display = []
    num=0
    def __init__(self, master):
        self.master = master
        self.queue = queue.Queue()
        Demo2.value = Demo1.data
        self.button = tkinter.Button(self.master,height=2,width=11, text="new",command=self.new).place(x=0,y=0)
        self.label = tkinter.Label(self.master, text="monitor", font=("Arial",20)).grid(row=0, columnspan=3)
        cols = ('aa','bb')
        self.treeview = ttk.Treeview(self.master, columns=cols)
        for col in cols:
            self.treeview.heading(col, text=col)
            self.treeview.column(col,minwidth=0,width=170)
        self.treeview.grid(row=1, column=0)
        self._img=tkinter.PhotoImage(file="green1.gif")
        self.aaa()
        
    def aaa(self):
                num_threads = 5 * multiprocessing.cpu_count()
                p = multiprocessing.dummy.Pool(num_threads)
                p.map(self.ping_func, [x for x in Demo2.value])
                self.process_incoming() 
                #threading.Timer(1.0, self.aaa).start()
                self.master.after(100, self.aaa)
                
    def ping_func(self,ip):   #Ping every ip and append the result 
            ping_result = []
            pingCmd = "ping -n 1 -w 1000 " + ip
            childStdout = os.popen(pingCmd)
            result = (childStdout.readlines())
            childStdout.close()
            ping_result.append(ip)
            if(any('Reply from' in i for i in result)):
                ping_result.append("success")
            else:
                ping_result.append("failed")
            self.queue.put(ping_result)  #Thread value to queue
            
    def process_incoming(self):   #add the ping result to treeview
        while self.queue.qsize():
            try:
                if Demo2.num<len(Demo1.data):
                    self._img=tkinter.PhotoImage(file="green1.gif")
                    self._img1=tkinter.PhotoImage(file="red.gif")
                    msg = self.queue.get_nowait()
                    Demo2.display.append(msg)  #adding queue value to variable(display)
                    if(len(Demo2.display)==len(Demo1.data)):      
                        self.treeview.insert("","end",values=(0,0,0,0,0))
                        self.treeview.delete(*self.treeview.get_children())
                        for i,(a,b) in enumerate(Demo2.display):
                            if(Demo2.display[i][1]=='success' ):
                                self.treeview.insert('', 'end',image=self._img, value=(a,b))
                            else:
                                self.treeview.insert('', 'end',image=self._img1, value=(a,b))
                        Demo2.num=Demo2.num+1
                        Demo2.display.clear()
                else:
                    Demo2.display.clear()
                    Demo2.num=0     
            except queue.Empty:  # Shouldn't happen.
                pass
            
    def periodic_call(self):
        self.master.after(200, self.periodic_call) # checking its contents periodically
        self.process_incoming()
        if not self.running:
            import sys
            sys.exit(1)       

    def new(self):
        self.master.destroy() # close the current window
        self.master = tkinter.Tk() # create another Tk instance
        self.app = Demo1(self.master) # create Demo2 window
        self.master.mainloop()

def main():
    root = tkinter.Tk()
    app = Demo1(root)
    root.mainloop()


if __name__ == '__main__':
    main()

Answer 1

主要问题是ping -w 1000 需要大量时间来运行，但Pool.map() 等待所有结果。你甚至可以在没有queue 的情况下运行results = p.map(...)（但使用return result），但它也可以阻止tkinter

您可以使用map_async() 运行它而无需等待结果。

我还使用starmap（或者更确切地说starmap_async()）向每个进程发送两个参数ip, queue。

我还进行了其他更改 - 即。重命名变量，将一些代码移动到__init__ 以仅创建一次（图像，Pool，Queue）。我还将 IP 列表作为参数 Window2(master, data) 发送到其他窗口并返回 Window1(master, data) - 所以我可以编辑这个列表。

BTW: 因为我在 Linux 上运行，所以我更改了 ping 的参数并检查不同的文本以测试它是否得到答案。

import os
import multiprocessing.dummy
import queue
import tkinter as tk
import tkinter.ttk as ttk

# --- classes ---

class Window1:
    
    def __init__(self, master, data=None):
        self.master = master
        
        self.data = data
        
        if self.data is None:
            self.data = []

        self.text = tk.Text(self.master, height=20, width=50)
        self.text.grid(row=1, column=1)
        
        self.button = tk.Button(self.master, height=3, width=10, text="OK", command=self.new_window)
        self.button.grid(row=2, column=1)

        # put self.data in Text
        #for item in self.data:
        #    self.text.insert('end', item + '\n')
        self.text.insert('end', '\n'.join(self.data))
            
    def new_window(self):
        text = self.text.get('1.0', 'end')
        
        # remove empty lines
        self.data = [item.strip() for item in text.split("\n") if item.strip()]
        
        self.master.destroy()
        
        root = tk.Tk()
        Window2(root, self.data)
        root.mainloop()
        
        
class Window2:
    
    def __init__(self, master, data):
        self.master = master

        # keep list
        self.data = data
        
        # create dictionary for results
        self.results = {ip: [ip, '???'] for ip in self.data}
        
        self.button = tk.Button(self.master, height=2, width=11, text='New', command=self.new)
        self.button.grid(row=0, column=0, sticky='w')

        self.label = tk.Label(self.master, text='monitor', font=("Arial", 20))
        self.label.grid(row=0, column=1)

        cols = ('IP','Result')
        
        self.treeview = ttk.Treeview(self.master, columns=cols)
        for col in cols:
            self.treeview.heading(col, text=col)
            self.treeview.column(col,minwidth=0,width=170)
        self.treeview.grid(row=1, column=0, columnspan=3)
        
        # create only once
        self._image_green = None # tk.PhotoImage(file="green1.gif")
        self._image_red   = None # tk.PhotoImage(file="red.gif")

        # to reduce number of processes for small `data`
        n = min(5, len(self.data))

        # create only once
        self.queue = queue.Queue()
        self.num_threads = n * multiprocessing.cpu_count()
        self.p = multiprocessing.dummy.Pool(self.num_threads)

        # to stop `after()`
        self.running = True        

        # run first time
        self.update_treeview()  # to display it before running processes

        self.run_processes()
        self.processes_incoming() # first create window to display it faster
        
    def run_processes(self):
        if self.running:
            self.p.starmap_async(self.ping, [(ip, self.queue) for ip in self.data])
            self.after_ID2 = self.master.after(500, self.run_processes)
        
    def ping(self, ip, queue):
        #print('start ping:', ip)
        
        #cmd = 'ping -n 1 -w 3 ' + ip
        cmd = 'ping -w 1 ' + ip  # Linux
        
        child_stdout = os.popen(cmd)
        result = child_stdout.readlines()
        child_stdout.close()
        
        #print('end ping:', ip)

        #if any('Reply from' in line for line in result):
        if any('bytes from' in line for line in result): # Linux
            value = [ip, 'success']
        else:
            value = [ip, 'failed']
            
        queue.put(value)
        
    def update_treeview(self):
        self.treeview.delete(*self.treeview.get_children())
        
        for ip in self.data:
            ip, value = self.results[ip]
            if value == 'success':
                image = self._image_green
            elif value == 'failed':
                image = self._image_red
            else:
                image = None

            #self.treeview.insert('', 'end', image=image, value=(ip, valueb))
            self.treeview.insert('', 'end', value=(ip, value))

    def processes_incoming(self):
       
       if self.running:

            # get all from queue
            new_values = False
            while self.queue.qsize():
            #while not self.queue.empty:
                data = self.queue.get_nowait()
                ip, value = data
                self.results[ip] = data
                new_values = True

            # update only if new values    
            if new_values:
                self.update_treeview()
                
            # repeate after 100ms    
            self.after_ID1 = self.master.after(100, self.processes_incoming) 

    def new(self):
        # to stop all `after()`
        self.running = False
        self.master.after_cancel(self.after_ID1)
        self.master.after_cancel(self.after_ID2)
        
        self.master.destroy()
        
        root = tk.Tk()
        Window1(root, self.data)
        root.mainloop()

# --- functions ---

def main():
    examples = [
        '127.0.0.1',    # localhost
        '10.0.0.1',     # IP in local network
        '192.168.0.1',  # IP in local network
        '8.8.8.8',      # Google DNS
        '8.8.4.4',      # Google DNS
    ]
    
    root = tk.Tk()
    Window1(root, examples)
    root.mainloop()

# --- main ---

if __name__ == '__main__':
    main()