python线程问题 threads can only be started once

图片说明

代码如下:

import tkinter as tk
from tkinter import ttk
from threading import Thread
import time

class main():
def method(self):
for i in range(3):
time.sleep(1)
print(i)

op = main()
runT = Thread(target=op.method)
win = tk.Tk()
win.title("Python")

def click():
runT.start()

action = ttk.Button(win, text="Click Me!", command=click) # 7
action.grid(column=0, row=0)
win.mainloop()

我想每次点击下按钮就执行一次,但是python线程只能执行一次 按钮第二次点击就报错threads can only be started once 请问如何才能解决呢?

4个回答

因为你只建立了一个进程,这个进程只能管理当前的一次操作。
因此可以每次点击的时候都重新建立一个进程,如下所示。

 import tkinter as tk
from tkinter import ttk
from threading import Thread
import time


class main:
    def newThread(self):
        Thread(target=self.method).start()

    def method(self):
        for i in range(3):
            time.sleep(1)
            print(i)

op = main()
win = tk.Tk()
win.title("Python")

def click():
    op.newThread()

action = ttk.Button(win, text="Click Me!", command=click) # 7
action.grid(column=0, row=0)
win.mainloop()

界面操作要在主线程,通过子线程执行界面操作会出问题,建议发消息

jeekmary
京城最明亮的少年 建议你用PyQt5
一年多之前 回复
qq_41760967
qq_41760967 高手看不懂 不好意思
一年多之前 回复

修改下click函数,具体如下
把以下两句代码添加到click函数
runT = Thread(target=op.method)
runT.start()

def click():
op = main()
runT = Thread(target=op.method)
runT.start()

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arcgis 地图发布之前一直运行正常 最近发布的地图访问不了,catalog中也无法对已经发布的地图进行重新启动,处于停止状态,很郁闷,为什么之前运行的好好的,都快一年了,突然出现这个问题呢?rnconfiguration mapserver can not be started
You Only Look Once Unified, Real-Time Object Detection.pdf
You Only Look Once Unified, Real-Time Object Detection.pdf
You Only Look Once: Unified, Real-Time Object Detection
yolo,目标检测经典论文
require once的问题
假如不同连接的请求,导致后续代码里require 或require_once "1.php"后,rnrn如果是require 是不是在处理不同连接业务时,1.php里的数据不共享?rnrequire_once的话,共享数据.?上一个连接修改了某个1.php里某个globe后,下次连接请求时会反应出来修改?
Java学习笔记69. 运行线程 RUN THREADS
前面总结了,线程是一种容器,运行代码的容器。这些容器都在更大的容器进程(Process)里。默认的启动的线程是main方法所在的线程,如果要使用多线程,就要启动它。有两种方法可以启动多线程:1. 通过创建线程对象,然后使用线程对象的start方法来启动线程2. 通过创建实现了Runnable接口的对象,再把此对象作为参数,传递给Thread类的构造方法,构造出Thread的一个实例,再使用这个实例...
1.3. Risks of Threads(使用线程带来的风险)
1.3. Risks of Threads(使用线程带来的风险) Java's built-in support for threads is a double-edged sword. While it simplifies the development of concurrent applications by providing language and library support ...
click once 的问题
我们项目组在作一个click once 的项目,在我同事的机器上发布了一个版本,但本周我发布的时候,却发现报了一个很奇怪的错,“SignTool 报告了一个错误“密钥集不存在。“,编译是通过的,但发布就是不成功,但到我原来同事的机器发布确实没问题,我始终不明白其中的原因,难道发布是会有类似于签名的东西吗,小弟对click once理解不深,求高人指点,谢谢rn
#pragma once 的问题。
#if !defined(AFX_MAINFRM_H__2A7D45A9_1608_11D5_A261_0050BA1A68C7__INCLUDED_)rn#define AFX_MAINFRM_H__2A7D45A9_1608_11D5_A261_0050BA1A68C7__INCLUDED_rnrn#if _MSC_VER > 1000rn#pragma oncern#endif // _MSC_VER > 1000rnrn...............rnrn#endif rnrn以上是VC的一个头文件定义方式。rn采用 #ifndef _XXX_rn #define _XXX_rn ........rn #endifrn已经可以避免头文件在整个工程中有多个副本。那么这里在里用 #pragma once 是为了什么情况用的呢?rn#pragma once 的意思好象也是为了避免某个文件在工程中有多个副本的宏。在这里都用到了到底是怎么回事呢?rnrn谢谢.rn
tomcat max threads得问题
使用tamcat4.1.27 运行过程中出现以下错误信息:rnrn2004-9-3 13:44:03 org.apache.tomcat.util.threads.ThreadPool logFullrn严重: All threads are busy, waiting. Please increase maxThreads or check the serrnvlet status75 75rnrnrn请问这个错误在可能是什么原因造成得?rnmaxThreads可以配置么?在什么地方配置?rnserrnvlet status75 是什么意思?rn谢谢rnrn
Getting Started with Python and Raspberry Pi.pdf
Raspberry PI是最小、最便宜的单板电脑之一,它已经占领了业余电子和编程领域,Python编程语言使它成为开始编码的完美平台。本书将从简要介绍Raspberry、PI和Python开始。我们将指导您使用必要的设备,如监视器、键盘、鼠标、电源等,帮助您设置Raspberry PI的正式文档。然后,它将深入了解Python编程的基础知识。稍后,它将关注其他Python任务,例如,与硬件接口、GUI编程等等。一旦您熟悉了基本编程,这本书就会教您如何开发Python/Raspberry PI应用程序。在这本书的末尾,您将能够使用Python开发Raspberry PI应用程序,并对Raspberry PI的Python编程有很好的理解。这本书是为那些不熟悉Python开发艺术的人而设计的,他们想了解他们的语言和许多其他的库,这些库允许您在短时间内启动和运行一个完整的应用程序。
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