Tkinter：通过单击按钮来调度顺序执行的线程

Question

我有一个Tkinter图形用户界面，每个按钮都使用线程调用不同的函数。我必须按顺序自动点击按钮。所以我使用一个单独的开始按钮，它将单击第一个按钮，等待相应函数的执行完成，然后单击下一个按钮，依此类推。在

当任何函数运行时，我使用线程来保持Progressbar的运行。在

我还将按钮文本的颜色从红色（尚未运行）更改为蓝色（正在运行）到绿色（已完成执行）。我知道我需要在某处使用join()，但它不起作用。在

当前代码一次运行所有的buttoninvoke()方法，而不是按顺序运行。在

import tkinter as tk
from tkinter import ttk

from threading import Thread
def sample_function():
    for i in range(1,10000) :
        print(i)

def run_function(name, func,btn_variable):
    # Disable all buttons
    btn_variable.configure(style = 'blue.TButton')
    processing_bar.start(interval=10)
    print(name, 'started')
    func()
    processing_bar.stop()
    print(name, 'stopped')
    btn_variable.configure(style = 'green.TButton')

def run_thread(name, func,btn_variable):
    Thread(target=run_function, args=(name, func,btn_variable)).start()


def prepare_clicked():
    run_thread('prepare', sample_function,prepare_btn)
    prepare_btn.configure(style = 'green.TButton')


def social_clicked():
    run_thread('social', sample_function,social_btn)
    social_btn.configure(style = 'green.TButton')


def anomaly_clicked():
    run_thread('anomaly', sample_function,anomaly_btn)
    anomaly_btn.configure(style = 'green.TButton')

def scoring_clicked():
    run_thread('scoring', sample_function,scoring_btn)
    scoring_btn.configure(style = 'green.TButton')

def dashboard_clicked():
    run_thread('dashboard', sample_function,dashboard_btn)
    dashboard_btn.configure(style = 'green.TButton')


def start_all():
    prepare_btn.invoke()
    anomaly_btn.invoke()
    social_btn.invoke()
    scoring_btn.invoke()
    dashboard_btn.invoke()



window = tk.Tk()
#window = tk.Toplevel()

topFrame = tk.Frame(window)
bottomFrame = tk.Frame(window)

# Tell the Frame to fill the whole window
topFrame.pack(fill=tk.BOTH, expand=1)
bottomFrame.pack(fill=tk.BOTH, expand=1)

# Make the Frame grid contents expand & contract with the window
topFrame.columnconfigure(0, weight=1)
for i in range(5):
    topFrame.rowconfigure(i, weight=1)

bottomFrame.rowconfigure(0, weight=1)
for i in range(3):
    bottomFrame.columnconfigure(i, weight=1)

ttk.Style().configure('blue.TButton', foreground='blue')
ttk.Style().configure('green.TButton', foreground='green')
ttk.Style().configure('red.TButton', foreground='red')


prepare_btn = ttk.Button(topFrame, command=prepare_clicked, text='Button 1',style = 'red.TButton')
anomaly_btn = ttk.Button(topFrame,command=anomaly_clicked, text='Button 2',style = 'red.TButton')
social_btn = ttk.Button(topFrame, command=social_clicked, text='Button 3',style = 'red.TButton')
scoring_btn = ttk.Button(topFrame, command=scoring_clicked, text='Button 4',style = 'red.TButton')
dashboard_btn = ttk.Button(topFrame, command=dashboard_clicked, text='Button 5',style = 'red.TButton')
commentary = ttk.Button(bottomFrame,text='START',width=10,command = start_all)
commentarylabel = ttk.Label(bottomFrame,text=' Commentary ',width=25)
processing_bar = ttk.Progressbar(bottomFrame, orient='horizontal', mode='indeterminate')

buttons = [prepare_btn, anomaly_btn, social_btn,scoring_btn,dashboard_btn]


prepare_btn.grid(row=0, column=0, columnspan=1, sticky='EWNS')
anomaly_btn.grid(row=1, column=0, columnspan=1, sticky='EWNS')
social_btn.grid(row=2, column=0, columnspan=1, sticky='EWNS')
scoring_btn.grid(row=3, column=0, columnspan=1, sticky='EWNS')
dashboard_btn.grid(row=4, column=0, columnspan=1, sticky='EWNS')
commentary.grid(row=0, column=0, columnspan=1, sticky='EWNS')
commentarylabel.grid(row=0,column = 1, columnspan=2, sticky='EWNS')
processing_bar.grid(row=0, column=3,columnspan=1, sticky='EWNS')

window.mainloop()

Answer 1

下面是一些演示如何做你想做的事情。它之所以有效，是因为在主线程以外的线程中运行的代码不会进行任何tkinter调用。为了让线程一个接一个地按顺序运行，它使用一个FIFOQueue表示每个线程的条目，并在最后一个线程完成后开始新的线程的运行。在

要按照start_all()函数中所做的那样，按照一定的顺序“调度”一系列步骤，只需put()按照它们应该在此job_queue的顺序执行每个步骤。在

这一切都是通过反复使用通用的^{}方法定期运行一个“polling”函数（名为poll）来完成的，该函数检查另一个线程当前是否正在执行，并相应地作出反应。在

在代码中，每个线程所做的处理被称为“步骤”或“作业”。在

from queue import Queue, Empty
import random
import tkinter as tk
from tkinter import ttk
import tkinter.messagebox as tkMessageBox
from threading import Thread
from time import sleep

random.seed(42)  # Generate repeatable sequence for testing.

ITERATIONS = 100
POLLING_RATE = 100  # millisecs.

# Global variables
cur_thread = None  # Current running thread.
cur_button = None
cur_name = None
job_queue = Queue()  # FIFO queue.

def sample_function():
    for i in range(1, ITERATIONS):
        print(i)
        sleep(0.01)  # Simulate slow I/O.

def start_thread(name, func, btn_variable):
    global cur_thread, cur_button

    if cur_thread is not None:
        tkMessageBox.showerror('Error', "You can't start a step when there"
                                        " are some already running.")
        return

    cur_thread = Thread(target=func)
    cur_button = btn_variable

    btn_variable.configure(style='blue.TButton')
    cur_thread.start()

def poll(window, processing_bar):
    global cur_thread, cur_button

    if cur_thread is not None:
        if cur_thread.is_alive():
            processing_bar.step()
        else:
            cur_thread.join() # Should be immediate.
            cur_thread = None
            processing_bar.stop()
            cur_button.configure(style='green.TButton')
            window.update()
    elif not job_queue.empty():  # More to do?
        try:
            job_info = job_queue.get_nowait()  # Non-blocking.
            start_thread(*job_info)
            processing_bar.start()
            window.update()
        except Empty:  # Just in case (shouldn't happen).
            pass

    window.after(POLLING_RATE, poll, window, processing_bar)

# Button commands.
def prepare_clicked():
    start_thread('prepare', sample_function, prepare_btn)

def social_clicked():
    start_thread('social', sample_function, social_btn)

def anomaly_clicked():
    start_thread('anomaly', sample_function, anomaly_btn)

def scoring_clicked():
    start_thread('scoring', sample_function, scoring_btn)

def dashboard_clicked():
    start_thread('dashboard', sample_function, dashboard_btn)

def start_all():
    global job_queue

    # Put info for each step in the job queue to be run.
    for job_info in (('prepare', sample_function, prepare_btn),
                     ('social', sample_function, social_btn),
                     ('anomaly', sample_function, anomaly_btn),
                     ('scoring', sample_function, scoring_btn),
                     ('dashboard', sample_function, dashboard_btn)):
        job_queue.put(job_info)
    # Start the polling.
    window.after(POLLING_RATE, poll, window, processing_bar)

####
window = tk.Tk()
#window = tk.Toplevel()

topFrame = tk.Frame(window)
bottomFrame = tk.Frame(window)

# Tell the Frame to fill the whole window
topFrame.pack(fill=tk.BOTH, expand=1)
bottomFrame.pack(fill=tk.BOTH, expand=1)

# Make the Frame grid contents expand & contract with the window
topFrame.columnconfigure(0, weight=1)
for i in range(5):
    topFrame.rowconfigure(i, weight=1)

bottomFrame.rowconfigure(0, weight=1)
for i in range(3):
    bottomFrame.columnconfigure(i, weight=1)

ttk.Style().configure('blue.TButton', foreground='blue')
ttk.Style().configure('green.TButton', foreground='green')
ttk.Style().configure('red.TButton', foreground='red')

prepare_btn     = ttk.Button(topFrame, command=prepare_clicked, text='Button 1', style='red.TButton')
anomaly_btn     = ttk.Button(topFrame, command=anomaly_clicked, text='Button 2', style='red.TButton')
social_btn      = ttk.Button(topFrame, command=social_clicked, text='Button 3', style='red.TButton')
scoring_btn     = ttk.Button(topFrame, command=scoring_clicked, text='Button 4', style='red.TButton')
dashboard_btn   = ttk.Button(topFrame, command=dashboard_clicked, text='Button 5', style='red.TButton')

commentary      = ttk.Button(bottomFrame, text='START', width=10, command=start_all)
commentarylabel = ttk.Label(bottomFrame, text=' Commentary ', width=25)
processing_bar  = ttk.Progressbar(bottomFrame, orient='horizontal', mode='indeterminate')

prepare_btn.grid    (row=0, column=0, columnspan=1, sticky='EWNS')
anomaly_btn.grid    (row=1, column=0, columnspan=1, sticky='EWNS')
social_btn.grid     (row=2, column=0, columnspan=1, sticky='EWNS')
scoring_btn.grid    (row=3, column=0, columnspan=1, sticky='EWNS')
dashboard_btn.grid  (row=4, column=0, columnspan=1, sticky='EWNS')

commentary.grid     (row=0, column=0, columnspan=1, sticky='EWNS')
commentarylabel.grid(row=0, column=1, columnspan=2, sticky='EWNS')
processing_bar.grid (row=0, column=3,columnspan=1, sticky='EWNS')

window.after(POLLING_RATE, poll, window, processing_bar)
window.mainloop()