How to remove NavigationToolbar2Tk from FigureCanvasTkAgg?

Question

I use a Tkinter button to plot my chart. When I click the button, the navigation toolbar is placed on the bottom of the screen. Every time when I click the button, it places a new navigation toolbar over the existing one. I would like to see only one navigation toolbar. I tried to add one more button and assign a function which removes the existing toolbar by using canvas.delete('all'). Clicking more times on Select button results more navigation toolbar.

Here is my code:

import os
import tkinter as tk
from tkinter import ttk
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import (FigureCanvasTkAgg,NavigationToolbar2Tk)

#command function for button1
def plotSelectedFile():
    filename = combobox1.get()
    txt_file = open(filename,'r')
    data = txt_file.readlines()
    plotY_values=[]
    for i in data:
        plotY_values.append(float(i))
    txt_file.close()
    fig = Figure(figsize = (6, 5), dpi = 100)
    plot1 = fig.add_subplot(111)
    plot1.plot(plotY_values)
    canvas = FigureCanvasTkAgg(fig, master = root)
    canvas.draw()
    canvas.get_tk_widget().place(x=300,y=100)
    toolbar = NavigationToolbar2Tk(canvas, root)

def removeCanvas():
    canvas.delete('all')


#list files in current folder (current eg. where this file saved)
#append files to empty list if it is .txt file
arr = os.listdir()
txt_file_list = []
for i in arr:
    if i[-3:] == 'txt':
    txt_file_list.append(i)

#####     INITILIZE TKINTER WINDOW     #####

#set window
root=tk.Tk()
root.title('Data plotter program')
w = root.winfo_screenwidth()
h = root.winfo_screenheight()
root.geometry("%dx%d+0+0" % (w, h))

#set widgets
combobox1 = ttk.Combobox(root,width=15)
combobox1.place(x=40,y=40)
combobox1['values']=txt_file_list
button1 = ttk.Button(root,text='Select',command=plotSelectedFile)
button1.place(x = 200, y = 40)
button2 = ttk.Button(root,text='Remove',command=removeCanvas)
button2.place(x = 300, y = 40)

root.mainloop()

Your function is working exactly as expected - it creates a new `canvas` and `toolbar` every time it was executed. The `canvas` are stacked on each other while `toolbar` keeps appending new ones to the bottom. — Henry Yik, Nov 02 '20 at 14:29
So first of all i have to delete canvas and toolbar in the function right before it creates a new one. But how? — murcsiktamas, Nov 02 '20 at 15:44
Have you considered re-using the same `canvas` and `toolbar` instead of destroying it? — Henry Yik, Nov 02 '20 at 15:53
So you mean removing canvas and toolbar from the function and paste it under my widgets (eg. button) ? It means only the plotting happens when I click on the Select button. This code should be outside of my function? canvas = FigureCanvasTkAgg(fig, master = root) canvas.draw() canvas.get_tk_widget().place(x=300,y=100) toolbar = NavigationToolbar2Tk(canvas, root) — murcsiktamas, Nov 02 '20 at 16:38
See [this](https://stackoverflow.com/questions/59001195/how-to-update-a-graph-created-by-matplotlib-in-tkinter/59004437#59004437) for a sample. — Henry Yik, Nov 02 '20 at 18:22

How to remove NavigationToolbar2Tk from FigureCanvasTkAgg?

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