I have now change my code and I have done the following. I have open a Tkinter toplevel, and worked on it: def OnButtonBress(self,) self.fig= matplotlip.figure.figure() (... here I have build the code to build my axis using the self.fig.add_subplot() function ) root=Tk.Toplevel() canvas = FigureCanvasTkAgg(self.fig, master=root) canvas.show() canvas.get_tk_widget().pack(side='top', fill='both', expand=1) toolbar = NavigationToolbar2TkAgg( canvas, root ) toolbar.update() canvas._tkcanvas.pack(side='top', fill='both', expand=1) But when I close the window, the same message... I tried to make some prints function to make debug in the backend_tkagg.py file whoever an destroy command is called. I have tried to print the id's of the self.__idle_callback to see if the randomNumber is the same, but when it plots the Tk.Window and my graphs, nothing has been printed. I want to ask, what is calling after the window has been destroyed? Because I have make code do destroy this window whenever I want. And when I call the function root.destroy() the above error message is printed to the shell. Best regards, A.Paiva -- View this message in context: http://matplotlib.1069221.n5.nabble.com/invalid-command-name-randomNumbercallit-tp42585p42588.html Sent from the matplotlib - users mailing list archive at Nabble.com.