Tkinter 重叠网格小部件

Question

everyone. I'm new to Python and trying to learn it as my future jobs will require me knowing it. I'm playing around with Tkinter, trying to get a pinging script to work. The result of this script will show a list of servers in column 0 and a list of whether it is up or down in column 1. I have it working except for one thing: the widgets overlap, causing this script to be a memory hog. For example, if the site "google.com" responds with "UP" and I take down my internet, it will show as "DOWN". However, as soon as a plug my internet back in, it will show as "UP" but I can see the remnants of the word "DOWN" behind the label. I've tried different ways to destroy the widget before every utilization but can not get it to work. I understand if my code is a little messy so I'm definitely open to criticism. Below is the code I have with a few example sites listed in the "host" variable:

import pyping
import Tkinter as tk
from Tkinter import *
import time

host = ["google.com", "yahoo.com", "espn.com"]

root = tk.Tk()

class PingTest:

    result = []
    resultfc = []

    def __init__(self, hostname, inc):
        self.hostname = hostname
        self.inc = inc
        self.ping(hostname)

    def results(self, result1, resultfc1):
        self.result = result1
        self.resultfc = resultfc1

    def ping(self, y):
        self.y = y
        q = ""
        try:
            x = pyping.ping(self.y, count=1)
            q = x.ret_code
        except Exception:
            pass
        finally:
            if q == 0:
                self.results("UP", "green")
            else:
                self.results("DOWN", "red")

        self.window()

    def window(self):

        self.label1 = Label(root, text=self.hostname)
        self.label2 = Label(root, text=self.result, fg=self.resultfc, bg="black")

        a = Label(root, text=self.hostname)
        b = Label(root, text=self.result, fg=self.resultfc, bg="black")
        b.update()
        b.update_idletasks()
        if b == TRUE:
            b.grid_forget() # These two lines don't seem to help my cause
            b.destroy()
        a.grid(row=self.inc, column=0)
        b.grid(row=self.inc, column=1)


while TRUE:
    i = 0
    for h in host:
        PingTest(h, i)
        i += 1
    time.sleep(1)

Answer 1

I would update labels instead of destroying them.

We can use threading to check each site without having to block the mainloop() . By creating a list of labels you can use the index of the list to set up the labels on your GUI and at the same time we can start a thread per object in list to check on the site status and return if site is up or down. I chose to use urllib and threading to make this work.

import tkinter as tk
import urllib.request
import threading
import time

host = ["google.com", "yahoo.com", "espn.com"]

class CheckURL:
    def __init__(self, host, widget):
        self.host = host
        self.widget = widget
        self.update_labels()

    def update_labels(self):
        if urllib.request.urlopen("http://www." + self.host).getcode() == 200:
            self.widget.config( text='UP', fg='green')
        else:
            self.widget.config(text='DOWN', fg='red')
        time.sleep(5)
        self.update_labels()

root = tk.Tk()
labels = []

for ndex, x in enumerate(host):
    tk.Label(root, text=x).grid(row=ndex, column=0)
    labels.append(tk.Label(root, text='DOWN', fg='red'))
    labels[-1].grid(row=ndex, column=1)
    threading._start_new_thread(CheckURL, (x, labels[-1]))

root.mainloop()