Don't override update() in NavigationToolbar2Tk.

anntzer · anntzer · commit 81066290bcc9 · 2020-04-14T10:29:02.000+02:00
... likely a remnant of the old NavigationToolbar1.

- self._axes is not used anywhere.
- the super().update clears the navstack and resets the history buttons,
  which shouldn't change the window focus (so the contextmanager does
  nothing) -- especially given that set_history_buttons isn't even
  implemented for the Tk toolbar.
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -624,11 +624,6 @@ def save_figure(self, *args):
         except Exception as e:
             tkinter.messagebox.showerror("Error saving file", str(e))
 
-    def update(self):
-        self._axes = self.canvas.figure.axes
-        with _restore_foreground_window_at_end():
-            NavigationToolbar2.update(self)
-
 
 class ToolTip:
     """
