Question

我是python编码的新手，我一直在从事可以根据所选颜色单击图像的项目。我一直在使用一个程序，当我单击“开始”按钮时，该程序将循环搜索50次。但是，我一直在尝试实现停止按钮，但是问题是当循环运行时，我的代码冻结了。有什么想法吗？

我听说过尝试线程化，但是它看起来非常复杂，而且我无法正确遵循与代码有关的任何教程。顺便说一下，搜索到的图像一直在测试我一直使用的存储在程序文件中的图像。

from imagesearch import *
import pyautogui
import tkinter as tk
from tkinter import *
from tkinter.ttk import *
import time
import threading


# ---Defined Programs---
def run():
    global enterColor
    enterColor = str(enterColorField.get())
    program(enterColor)


def program(color):
    whitePos = imagesearch_numLoop(str(color) + ".PNG", 0, 50)
    pyautogui.moveTo(whitePos[0] + 20, whitePos[1] + 10)
    pyautogui.click()


def stop():
    print("Placeholder")


# ---Main Runner---
window = tk.Tk()
window.geometry("250x250")
window.configure(background="#181b54")

app = tk.Frame(window)
app.grid()

enterColorLabel = tk.Label(window, text="Enter Color:", bg="#181b54", fg="white")
enterColorLabel.place(x=10, y=50)

enterColorField = Combobox(window)
enterColorField['values'] = ("Black", "White")
enterColorField.current("0")  # set the selected item
enterColorField.place(x=10, y=70)

submitButton = tk.Button(window, text="Start", bg="#66ff00", command=run)
submitButton.place(x=10, y=130)

stopButton = tk.Button(window, text="Stop", bg="red", command=stop)
stopButton.place(x=50, y=130)

window.mainloop()


#---New Python Script---
import cv2
import numpy as np
import pyautogui
import random
import time

def imagesearch_numLoop(image, timesample, maxSamples, precision=0.8):
    pos = imagesearch(image, precision)
    count = 0
    while pos[0] == -1:
        print(image+" not found, waiting")
        count = count + 1
        if count>maxSamples:
            break
        pos = imagesearch(image, precision)
    return pos

每当单击开始时，整个代码就会冻结。我什至无法（x）。

Answer 1

一个简单的答案是您不能在GUI设计中使用while循环。

但是您可以改用方法.after(delay, callback=None)。

这里是一个例子：

from tkinter import *

root = Tk()

def loop():
    print("Hi!")
    root.after(1000, loop) # 1000 is equal to 1 second.

root.after(1000, loop) # This line is to call loop() in 1 second.
root.mainloop()

Answer 2

这是一个希望简单的多处理配方，将为您服务。我们将有三个主要功能。首先将是一个示例循环，您可以将处理放入其中。我在函数中包含了参数，以向您展示使用多处理时可以传递args和kwargs。

def loop(a, b, c, d):
     # Will just sleep for 3 seconds.. simulates whatever processing you do.
    time.sleep(3)
    return

接下来是一个函数，我们将使用该函数对多处理进程进行排队。

def queue_loop():
    p = multiprocessing.Process(target = loop, 
                                args = (1, 2),
                                kwargs = {"c": 3, "d": 4})
    # You can pass args and kwargs to the target function like that
    # Note that the process isn't started yet. You call p.start() to activate it.
    p.start()
    check_status(p) # This is the next function we'll define.
    return

然后，您可能会对了解整个过程的执行状态感兴趣。例如，有时希望在运行命令时禁用某些按钮。

def check_status(p):
    """ p is the multiprocessing.Process object """
    if p.is_alive(): # Then the process is still running
        label.config(text = "MP Running")
        mp_button.config(state = "disabled")
        not_mp_button.config(state = "disabled")
        root.after(200, lambda p=p: check_status(p)) # After 200 ms, it will check the status again.
    else:
        label.config(text = "MP Not Running")
        mp_button.config(state = "normal")
        not_mp_button.config(state = "normal")
    return

将所有内容放到一个片段中

import tkinter as tk
import multiprocessing
import time

def loop(a, b, c, d):
     # Will just sleep for 3 seconds.. simulates whatever processing you do.
    time.sleep(3)
    return

def queue_loop():
    p = multiprocessing.Process(target = loop, 
                                args = (1, 2),
                                kwargs = {"c": 3, "d": 4})
    # You can pass args and kwargs to the target function like that
    # Note that the process isn't started yet. You call p.start() to activate it.
    p.start()
    check_status(p) # This is the next function we'll define.
    return

def check_status(p):
    """ p is the multiprocessing.Process object """
    if p.is_alive(): # Then the process is still running
        label.config(text = "MP Running")
        mp_button.config(state = "disabled")
        not_mp_button.config(state = "disabled")
        root.after(200, lambda p=p: check_status(p)) # After 200 ms, it will check the status again.
    else:
        label.config(text = "MP Not Running")
        mp_button.config(state = "normal")
        not_mp_button.config(state = "normal")
    return


if __name__ == "__main__":
    root = tk.Tk()
    mp_button = tk.Button(master = root, text = "Using MP", command = queue_loop)
    mp_button.pack()
    label = tk.Label(master = root, text = "MP Not Running")
    label.pack()
    not_mp_button = tk.Button(master = root, text = "Not MP", command = lambda: loop(1,2,3,4))
    not_mp_button.pack()
    root.mainloop()

结果是，当您单击“使用MP”按钮时，将禁用命令按钮，并且将在不冻结UI的情况下启动该过程。单击“非MP”按钮将启动“正常”之类的功能，并且将冻结您的UI，就像您在自己的代码中注意到的那样。

Tkinter GUI在运行循环时冻结

2 个答案: