Python：執行緒和tkinter-有解無憂

我正在嘗試在 tkinter GUI 中不斷更新 matlibplots，同時能夠單擊按鈕來暫停/繼續/停止更新繪圖。我嘗試過使用執行緒，但它們似乎沒有并行執行（例如，正在執行資料執行緒但繪圖沒有得到更新單擊按鈕被忽略）。為什么它不起作用？

# Import Modules
import tkinter as tk
from threading import *
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import (FigureCanvasTkAgg, NavigationToolbar2Tk)
from scipy.fft import fft
import numpy as np
import time
import random

# global variables
state = 1             # 0 starting state; 1 streaming; 2 pause; -1 end and save
x = [0]*12
y = [0]*12

# Thread buttons and plots separately
def threading():
    state = 1
    
    t_buttons = Thread(target = buttons)
    t_plots = Thread(target = plots)
    t_data = Thread(target = data)
    
    t_buttons.start()
    t_plots.start()
    t_data.start()
    
def hex_to_dec(x, y):
    for i in range(0, 12):
        for j in range(0, len(y)):
            x[i][j] = int(str(x[i][j]), 16)
            y[i][j] = int(str(y[i][j]), 16)
    
def data():
    fig1, axs1 = main_plot()
    fig2, axs2 = FFT_plot()
    # To be replaced with actual Arduino data
    while(state!=-1):
        for i in range(0, 12):
            x[i] = [j for j in range(101)]
            y[i] = [random.randint(0, 10) for j in range(-50, 51)]
        for i in range(0, 12):
            for j in range(0, len(y)):
                x[i][j] = int(str(x[i][j]), 16)
                y[i][j] = int(str(y[i][j]), 16)

# create buttons
def stream_clicked():
    state = 1
    print("clicked")
    
def pause_clicked():
    state = 2
    print("state")
    
def finish_clicked():
    state = -1
    
    
def buttons():
    continue_button = tk.Button(window, width = 30, text = "Stream data" , 
                              fg = "black", bg = '#98FB98', command = stream_clicked)
    continue_button.place(x = window.winfo_screenwidth()*0.2, y = 0)

    pause_button = tk.Button(window, width = 30, text = "Pause streaming data" , 
                             fg = "black", bg = '#FFA000', command = pause_clicked)
    pause_button.place(x = window.winfo_screenwidth()*0.4, y = 0)

    finish_button = tk.Button(window, width = 30, text = "End session and save", 
                              fg = 'black', bg = '#FF4500', command = finish_clicked())
    finish_button.place(x = window.winfo_screenwidth()*0.6, y = 0)
    
def plots():
    fig1, axs1 = main_plot()
    fig2, axs2 = FFT_plot()
    
    if state==1:
        print("update")
        for i in range(0, 12):
            axs1[i].plot(x[i], y[i], 'blue')
            axs1[i].axes.get_yaxis().set_ticks([0], labels = ["channel  "   str(i 1)])
            axs1[i].grid(True)
            axs1[i].margins(x = 0)
        
        fig1.canvas.draw()
        fig1.canvas.flush_events()
        for i in range(0, 12):
            axs1[i].clear()
        for i in range(0, 12):
            axs2.plot(x[i], fft(y[i]))
        plt.title("FFT of all 12 channels", x = 0.5, y = 1)
        
        fig2.canvas.draw()
        fig2.canvas.flush_events()
        axs2.clear()

def main_plot():
    plt.ion()
    
    fig1, axs1 = plt.subplots(12, figsize = (10, 9), sharex = True)
    fig1.subplots_adjust(hspace = 0)
    # Add fixed values for axis
    
    canvas = FigureCanvasTkAgg(fig1, master = window)  
    canvas.draw()
    canvas.get_tk_widget().pack()
    canvas.get_tk_widget().place(x = 0, y = 35)
    
    return fig1, axs1
    
def update_main_plot(fig1, axs1):
    if state==1:
        for i in range(0, 12):
            axs1[i].plot(x[i], y[i], 'blue')
            axs1[i].axes.get_yaxis().set_ticks([0], labels = ["channel  "   str(i 1)])
            axs1[i].grid(True)
            axs1[i].margins(x = 0)
        axs1[0].set_title("Plot recordings", x = 0.5, y = 1)
        
        fig1.canvas.draw()
        fig1.canvas.flush_events()
        for i in range(0, 12):
            axs1[i].clear()
    
    
def FFT_plot():
    # Plot FFT figure 
    plt.ion()
    
    fig2, axs2 = plt.subplots(1, figsize = (7, 9))
    # Add fixed values for axis
    
    canvas = FigureCanvasTkAgg(fig2, master = window)  
    canvas.draw()
    canvas.get_tk_widget().pack()
    canvas.get_tk_widget().place(x = window.winfo_screenwidth()*0.55, y = 35)
    
    return fig2, axs2


def update_FFT_plot(fig2, axs2):
    # Update FFT plot
    for i in range(0, 12):
        axs2.plot(x[i], fft(y[i]))
    plt.title("FFT", x = 0.5, y = 1)
    
    fig2.canvas.draw()
    fig2.canvas.flush_events()
    axs2.clear()

# create root window and set its properties
window = tk.Tk()
window.title("Data Displayer")
window.geometry("%dx%d" % (window.winfo_screenwidth(), window.winfo_screenheight()))
window.configure(background = 'white')

threading()

window.mainloop()

*** 有時它在沒有任何訊息的情況下無法正常作業，有時我還會收到“RuntimeError：主執行緒不在主回圈中”***

uj5u.com熱心網友回復：

公平地說，您代碼中的所有函式都極有可能導致分段錯誤，而其他不會導致分段錯誤的函式根本不起作用，很難解釋出了什么問題。

定義全域變數，就global好像你要修改它們一樣
window.after通過重復使用該方法更新主執行緒中的 GUI 。
只有從您的微控制器讀取應該在單獨的執行緒中完成。
Tkinter 物件的創建應該在主執行緒中完成，只允許在其他執行緒中進行更新，但它不是執行緒安全的，所以雖然它可能作業但有時會導致一些奇怪的行為或錯誤。
呼叫 matplotlib 之類的函式ion會flush_events導致錯誤，因為這些是針對 matplotlib 互動式畫布的，而不是針對 tkinter 畫布的。
執行緒有一個非常艱難的學習曲線，所以在你嘗試使用執行緒之前問問自己“我真的需要執行緒嗎”和“有什么方法可以不使用執行緒”，因為一旦你開始使用執行緒，你就不再使用 python 的“安全代碼”，盡管付出了所有努力，但執行緒不能安全地用于任何任務，由您來確保它們的安全，老實說，這里不需要執行緒，除非您從微控制器讀取 1 GB/s。
不要在狀態中使用數字，它不是 Pythonic，它會使讀者感到困惑，并且與使用 Enums 相比，它沒有性能優勢。
程式是增量構建的，而不是從多個作業片段中復制粘貼，因為當代碼的多個部分沒有被驗證為作業時，更難跟蹤錯誤來自哪里。

# Import Modules
import tkinter as tk
from threading import *
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import (FigureCanvasTkAgg, NavigationToolbar2Tk)
from scipy.fft import fft
import numpy as np
import time
import random
from enum import Enum,auto

UPDATE_INTERVAL_MS = 300

class States(Enum):
    STREAM = auto()
    PAUSE = auto()
    SAVE = auto()
    START = auto()


# global variables
state = States.START  # check States Enum
x = [[0]]*12
y = [[0]]*12


# Thread buttons and plots separately
def threading():
    global state
    global window
    state = States.STREAM

    buttons()
    plots()
    data()
    t_grab_data = Thread(target=grab_data_loop,daemon=True)
    t_grab_data.start()
    # t_buttons = Thread(target=buttons)
    # t_plots = Thread(target=plots)
    # t_data = Thread(target=data)
    #
    # t_buttons.start()
    # t_plots.start()
    # t_data.start()


def hex_to_dec(x, y):
    for i in range(0, 12):
        for j in range(0, len(y)):
            x[i][j] = int(str(x[i][j]), 16)
            y[i][j] = int(str(y[i][j]), 16)


def data():
    global fig1,axs1,fig2,axs2
    fig1, axs1 = main_plot()
    fig2, axs2 = FFT_plot()
    # To be replaced with actual Arduino data
    window.after(UPDATE_INTERVAL_MS,draw_data_loop)


def grab_data_loop():
    while state != States.SAVE:
        for i in range(0, 12):
            x[i] = [j for j in range(101)]
            y[i] = [random.randint(0, 10) for j in range(-50, 51)]
        for i in range(0, 12):
            for j in range(0, len(y)):
                x[i][j] = int(str(x[i][j]), 16)
                y[i][j] = int(str(y[i][j]), 16)
        time.sleep(0.1)  # because we are not reading from a microcontroller

def draw_data_loop():
    if state == States.STREAM:
        update_main_plot(fig1, axs1)
        update_FFT_plot(fig2, axs2)
    window.after(UPDATE_INTERVAL_MS,draw_data_loop)


# create buttons
def stream_clicked():
    global state
    state = States.STREAM
    print("clicked")


def pause_clicked():
    global state
    state = States.PAUSE
    print("state")


def finish_clicked():
    global state
    state = States.SAVE
    window.destroy()


def buttons():
    continue_button = tk.Button(window, width=30, text="Stream data",
                                fg="black", bg='#98FB98', command=stream_clicked)
    continue_button.place(x=window.winfo_screenwidth() * 0.2, y=0)

    pause_button = tk.Button(window, width=30, text="Pause streaming data",
                             fg="black", bg='#FFA000', command=pause_clicked)
    pause_button.place(x=window.winfo_screenwidth() * 0.4, y=0)

    finish_button = tk.Button(window, width=30, text="End session and save",
                              fg='black', bg='#FF4500', command=finish_clicked)
    finish_button.place(x=window.winfo_screenwidth() * 0.6, y=0)


def plots():
    global state
    fig1, axs1 = main_plot()
    fig2, axs2 = FFT_plot()

    if state == States.STREAM:
        print("update")
        for i in range(0, 12):
            axs1[i].plot(x[i], y[i], 'blue')
            axs1[i].axes.get_yaxis().set_ticks([0], labels=["channel  "   str(i   1)])
            axs1[i].grid(True)
            axs1[i].margins(x=0)

        # fig1.canvas.draw()
        # fig1.canvas.flush_events()
        # for i in range(0, 12):
        #     axs1[i].clear()
        for i in range(0, 12):
            axs2.plot(x[i], np.abs(fft(y[i])))
        plt.title("FFT of all 12 channels", x=0.5, y=1)

        # fig2.canvas.draw()
        # fig2.canvas.flush_events()
        # axs2.clear()


def main_plot():
    # plt.ion()
    global canvas1
    fig1, axs1 = plt.subplots(12, figsize=(10, 9), sharex=True)
    fig1.subplots_adjust(hspace=0)
    # Add fixed values for axis

    canvas1 = FigureCanvasTkAgg(fig1, master=window)
    # canvas.draw()
    canvas1.get_tk_widget().pack()
    canvas1.get_tk_widget().place(x=0, y=35)

    return fig1, axs1


def update_main_plot(fig1, axs1):
    if state == States.STREAM:
        for i in range(0, 12):
            axs1[i].clear()
        for i in range(0, 12):
            axs1[i].plot(x[i], y[i], 'blue')
            axs1[i].axes.get_yaxis().set_ticks([0], labels=["channel  "   str(i   1)])
            axs1[i].grid(True)
            axs1[i].margins(x=0)
        axs1[0].set_title("Plot recordings", x=0.5, y=1)
        canvas1.draw()
        # fig1.canvas.draw()
        # fig1.canvas.flush_events()



def FFT_plot():
    # Plot FFT figure
    # plt.ion()
    global canvas2
    fig2, axs2 = plt.subplots(1, figsize=(7, 9))
    # Add fixed values for axis

    canvas2 = FigureCanvasTkAgg(fig2, master=window)
    # canvas.draw()
    canvas2.get_tk_widget().pack()
    canvas2.get_tk_widget().place(x=window.winfo_screenwidth() * 0.55, y=35)

    return fig2, axs2


def update_FFT_plot(fig2, axs2):
    # Update FFT plot
    if state == States.STREAM:
        axs2.clear()
        for i in range(0, 12):
            axs2.plot(x[i], np.abs(fft(y[i])))
        plt.title("FFT", x=0.5, y=1)
        canvas2.draw()
    # fig2.canvas.draw()
    # fig2.canvas.flush_events()
    # axs2.clear()


# create root window and set its properties
window = tk.Tk()
window.title("Data Displayer")
window.geometry("%dx%d" % (window.winfo_screenwidth(), window.winfo_screenheight()))
window.configure(background='white')

threading()

window.mainloop()

# put saving logic here

轉載請註明出處，本文鏈接：https://www.uj5u.com/qiye/523273.html

標籤：Python多线程tkinter

上一篇：如何將implFnTrait物件傳遞給多個執行緒，例如使用執行緒池

下一篇：同一程式中的馬虎計數器和多個鎖