popup windows with matplotlib figure in tkinter

Question

When I insert a matplotlib figure in my tkinter window, when I start my program, extra popup windows appear. They do not affect the functionality of my GUI, but they are a bit annoying.

I have written a basic script that shows the problem. I run this through Spyder:

import tkinter as tk
import matplotlib
matplotlib.use("TkAgg")

from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
from matplotlib.pyplot import figure as Figure
from matplotlib import pyplot as plt

class MyGUI(tk.Tk):
    def __init__(self,master):
        self.f=Figure(figsize=(5,5),dpi=100)
        self.fig, self.ax= plt.subplots()

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


        self.toolbar=NavigationToolbar2Tk(self.canvas,master)
        #self.toolbar.update()
        self.canvas._tkcanvas.pack(padx=20, pady=20)

root =tk.Tk()
window=MyGUI(root)
root.mainloop()

When I run this, I get three windows. One is the root window that shows an empty graph and a toolbar (labeled 'tk'). This is the only window that I want. Then I get a 'Figure 1' window with a toolbar and a 'Figure 2' window with a graph and toolbar.

From commenting out the second half of the init method, it looks like the problem comes from this part.

self.f=Figure(figsize=(5,5),dpi=100)
self.fig, self.ax= plt.subplots()

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

However, I am quite new to object oriented programming and tkinter, and therefore not experienced enough to figure out what the mistake is. Any ideas?

Answer 1

You are creating two figures. One of them is created via pyplot. One shouldn't try to embedd a pyplot figure inside a custom GUI. Remove pyplot completely and create only a single figure.

import tkinter as tk
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
from matplotlib.figure import Figure

class MyGUI(tk.Tk):
    def __init__(self,master):
        self.fig=Figure(figsize=(5,5),dpi=100)
        self.ax = self.fig.add_subplot(111)

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

        self.toolbar=NavigationToolbar2Tk(self.canvas,master)
        #self.toolbar.update()
        self.canvas._tkcanvas.pack(padx=20, pady=20)

root =tk.Tk()
window=MyGUI(root)
root.mainloop()