matplotlib · QuLogic · Sep 9, 2020 · Sep 9, 2020
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -14,7 +14,7 @@
 from matplotlib import backend_tools, cbook
 from matplotlib.backend_bases import (
    _Backend, FigureCanvasBase, FigureManagerBase, NavigationToolbar2,
-    StatusbarBase, TimerBase, ToolContainerBase, cursors)
+    StatusbarBase, TimerBase, ToolContainerBase, cursors, _Mode)
 from matplotlib._pylab_helpers import Gcf
 from matplotlib.figure import Figure
 from matplotlib.widgets import SubplotTool
@@ -538,6 +538,23 @@ def destroy(self, *args):
        del self.message
        tk.Frame.destroy(self, *args)

+    def _update_buttons_checked(self):
+        # sync button checkstates to match active mode
+        for text, mode in [('Zoom', _Mode.ZOOM), ('Pan', _Mode.PAN)]:
+            if text in self._buttons:
+                if self.mode == mode:
+                    self._buttons[text].select()  # NOT .invoke()
+                else:
+                    self._buttons[text].deselect()
+
+    def pan(self, *args):
+        super().pan(*args)
+        self._update_buttons_checked()
+
+    def zoom(self, *args):
+        super().zoom(*args)
+        self._update_buttons_checked()
+
    def set_message(self, s):
        self.message.set(s)