在 Tkinter 中执行函数期间的程序冻结 [英] Program freezing during the execution of a function in Tkinter

问题描述

我为我的一个脚本创建了一个小图形用户界面.一切正常.

I've created a little GUI for one of my scripts. All is working well.

当我点击一个 Button 时，它会启动一个大功能，解析来自某些网站的大量数据.

When I click on one Button, it launches a big function that is parsing a lot of data from some websites.

但是一旦我点击了按钮，程序就会冻结，直到函数完全运行.一切正常，但为什么我的 GUI 在函数执行期间冻结.我想打印一个小进度条，但这是不可能的.

But once I've clicked on the Button, the program Freezes until the function is run entirely. All is working fine, but why is my GUI freezing during the execution of the function. I'd like to print a little progress bar, but it's not possible.

这是程序的一部分:

    self.Button1 = Button(self.MENU, text="IELTS", command=self.My_Command)
    self.Button1.grid(row=0, column=0,sticky=W+E)

def My_Command(self):

    ## HERE WE LAUNCH THE FUNCTION
    Module_1.main() # My Big Function from another file

    self.Button1.config(text="DONE")

在执行 Module_1.main() 期间我无法做/打印任何事情……GUI 完全冻结.

I can't do/print anything durint the execution of Module_1.main() ... the GUI is totally freezed.

Module_1.main() 函数是一个线程解析器(解析来自两个网站的一些数据)，一般需要2分钟才能运行.如果有人有想法能够在执行此函数所需的 2 分钟内与程序进行交互，那将非常有帮助.

The Module_1.main() function is a threaded parser (parsing some data from two websites), it takes generally 2 minutes to be ran. If someone have an idea to be able to interact with the program during the 2 minutes needed for the execution of this function, it would be very helpful.

推荐答案

Tkinter 是单线程的.通过事件循环，每次旅行都会发生屏幕更新.任何时候你有一个长时间运行的命令，你都会阻止事件循环完成迭代，从而阻止事件的处理，从而阻止重绘.

Tkinter is single threaded. Screen updates happen on each trip through the event loop. Any time you have a long running command you are preventing the event loop from completing an iteration, thus preventing the processing of events, thus preventing redraws.

您唯一的解决方案是 a) 为长时间运行的命令使用一个线程，b) 为长时间运行的命令使用一个进程，或 c) 将命令分成小块，每个小块都可以在几毫秒内运行，这样你可以在事件循环的后续迭代期间运行一个块.您还有另一种解决方案，即定期调用小部件的 update_idletasks 方法，但这与其说是修复，不如说是一种变通方法.

Your only solution is a) use a thread for the long running command, b) use a process for the long running command, or c) break the command up into small chunks that each can be run in a few ms so you can run one chunk during subsequent iterations of the event loop. You have one other solution which is to call the update_idletasks method of a widget periodically, but that's more of a workaround than a fix.

请记住，Tkinter 不是线程安全的，因此使用线程需要格外小心.您只能从主线程调用小部件上的方法，这意味着其他线程必须通过线程安全队列与主线程通信.

Bear in mind that Tkinter is not thread safe, so using threads requires extra care. You can only call methods on widgets from the main thread, which means other threads must communicate with the main thread via a thread-safe queue.

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