在tkinter中积分图给出更新idletasks错误

Question

I'm trying to create a super simple GUI and integrate a plot on it. I managed to integrate the plot but I have the Error:

AttributeError: 'NoneType' object has no attribute 'update_idletasks'

This question refers to the problem, but the answer doesn't really solve the problem of the update idletasks

My code is super simple, just two labels in a grid and I want t plot in the third row.

from tkinter import Label, Tk
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg


class MyGUI:
    def __init__(self):
        self.window = Tk()
        self.window.geometry('420x400')
        self.populate_elements()
        self.window.mainloop()

    def populate_elements(self):
        Label(self.window, text="Hello").grid(column=0, row=0)
        Label(self.window, text="My text").grid(column=0, row=1)

        fig = plt.Figure(figsize=(2, 2), dpi=100)
        ax = fig.add_subplot(111)
        ax.plot([1, 2, 3, 4, 5, 6, 7, 8], [5, 6, 1, 3, 8, 9, 3, 5])

        canvas = FigureCanvasTkAgg(fig)
        canvas.get_tk_widget().grid(column=0, row=2)


if __name__ == '__main__':
    MyGUI()

Answer 1

Matplotlib has an example about embedding in tk: https://matplotlib.org/3.1.1/gallery/user_interfaces/embedding_in_tk_sgskip.html

If you stick to it, you will find that you need to use

canvas = FigureCanvasTkAgg(fig, master=self.window)