“Gui”对象没有属性“after”

Question

我使用了我的工作 tkinter 代码（仅绘制了窗口/按钮等），并尝试从此处已批准的答案中添加一些代码：用于在窗口上打印串行数据的 python 代码。

批准的答案本身只需很小的修改即可工作，但添加到我的代码中时，我收到错误“'Gui'对象没有属性'after'”

我不明白的是为什么在 Gui 类中而不是在 process_serial 方法中查找属性“after”。

from tkinter import *
from tkinter import ttk

import serial
import threading
import queue

class SerialThread(threading.Thread):
    def __init__(self, queue):
        threading.Thread.__init__(self)
        self.queue = queue
    def run(self):
        s = serial.Serial('COM11',115200)
        while True:
            if s.inWaiting():
                text = s.readline(s.inWaiting())
                self.queue.put(text)

class Gui():
    def __init__(self, master):
        ###MAIN FRAME###
        mainFrame = Frame(master, width=50000, height=40000)
        mainFrame.pack(fill = BOTH, expand = 1)

        ###LIST FRAME###
        listFrame = Frame(mainFrame)
        listFrame.pack(side = TOP, fill = BOTH, expand = 1)

        self.sensorList = ttk.Treeview(listFrame)

        self.sensorList["columns"]=("MAC","Type","Value","Voltage","Firmware","Rate","RSSI")
        self.sensorList.column("MAC", width=200, minwidth=200)
        self.sensorList.column("Type", width=100, minwidth=100)
        self.sensorList.column("Value", width=100, minwidth=100)
        self.sensorList.column("Voltage", width=100, minwidth=100)
        self.sensorList.column("Firmware", width=100, minwidth=100)
        self.sensorList.column("Rate", width=100, minwidth=100)
        self.sensorList.column("RSSI", width=100, minwidth=100)
        self.sensorList.heading("MAC", text="MAC")
        self.sensorList.heading("Type", text="Type")
        self.sensorList.heading("Value", text="Value")
        self.sensorList.heading("Voltage", text="Voltage")
        self.sensorList.heading("Firmware", text="Firmware")
        self.sensorList.heading("Rate", text="Rate")
        self.sensorList.heading("RSSI", text="RSSI")

        self.sensorList.pack(fill = BOTH, expand = 1,  pady=5, padx=5)

        ###TEXT AREA FRAME###
        textAreaFrame = Frame(mainFrame)
        textAreaFrame.pack(side = TOP, fill = BOTH, expand = 1)

        self.textArea = Text(textAreaFrame)
        self.textArea.pack(fill = BOTH, expand = 1,  pady=5, padx=5)

        ###INPUT FRAME###
        inputFrame = Frame(mainFrame)
        inputFrame.pack(side = BOTTOM, fill = X, expand = 0)

        self.input = Entry(inputFrame)
        self.input.pack(side=LEFT, fill = X, expand = 1,  pady=5, padx=5)

        self.comboAction = ttk.Combobox(inputFrame)
        self.comboAction.pack(side = LEFT, pady=5, padx=5)

        self.comboDevice = ttk.Combobox(inputFrame)
        self.comboDevice.pack(side = LEFT, pady=5, padx=5)

        self.sendButton = Button(
            inputFrame, text="SEND", command=mainFrame.quit
        )

        self.sendButton.pack(side=LEFT,pady=5, padx=5)

        #self.button = Button(
        #   mainFrame, text="QUIT", fg="red", command=mainFrame.quit
        #)
        #self.button.pack(side=LEFT)

        #self.hi_there = Button(mainFrame, text="Hello", command=self.say_hi)
        #self.hi_there.pack(side=LEFT)

        ###AFFIX MINIMUM SIZE OF MAIN WINDOW TO PREVENT POOR SIZING###
        master.update()
        master.minsize(root.winfo_width(), root.winfo_height())
        master.minsize(master.winfo_width(), master.winfo_height())

        ###SERIAL PORT###
        self.queue = queue.Queue()
        thread = SerialThread(self.queue)
        thread.start()
        self.process_serial()

    def process_serial(self):
        while self.queue.qsize():
            try:
                self.textArea.delete(1.0, 'end')
                self.textArea.insert('end', self.queue.get())
            except Queue.Empty:
                pass
        self.after(100, self.process_serial)



    def say_hi(self):
        s = self.input.get()
        print ("hi there, everyone!" + s)

root = Tk()

gui = Gui(root)

root.mainloop()
root.destroy() # optional; see description below

Answer 1

罪魁祸首是 process_serial 函数中的这一行：

self.after(100, self.process_serial)

这里的 self 变量指的是 Gui 对象，而不是具有 'after' 函数的 tkinter 对象。

您的代码与链接问题中的代码不匹配。您的类没有扩展 tkinter 对象。答案中的类扩展了 tkinter Tk 对象，如下所示：

class App(tk.Tk):

从而从Tk类继承函数。

要在代码中解决此问题，请将 process_serial 函数中的 self 替换为 tkinter 对象，例如 self.textArea。

self.textArea.after(100, self.process_serial)

或者，您可以像链接的答案中一样对 tk.Tk 进行子类化。但我在这里没有看到额外的好处。