Added API note, enhanced gallery example, applied fix

Impaler343 · daniilS · Impaler343 · commit cc4a2f8eebd9 · 2025-12-13T16:47:19.000+05:30
Co-authored-by: daniilS &lt;daniil.soloviev@gmail.com&gt;
diff --git a/doc/api/next_api_changes/behavior/30852-PR.rst b/doc/api/next_api_changes/behavior/30852-PR.rst
@@ -0,0 +1,10 @@
+Default focus behavior of ``FigureCanvasTkAgg``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Previously, when a `.FigureCanvasTkAgg` object was created, focus was set to the
+canvas by default. Now, focus is not set anymore. If focus is desired on the canvas,
+it can be set explicitly after creation using the `focus_set()` method of Tkinter
+widgets.
+
+See :doc:`../../../gallery/user_interfaces/embedding_in_tk_sgskip` for an example of
+focus-setting in an embedded Matplotlib figure in a Tkinter application.
diff --git a/galleries/examples/user_interfaces/embedding_in_tk_sgskip.py b/galleries/examples/user_interfaces/embedding_in_tk_sgskip.py
@@ -62,4 +62,7 @@ def update_frequency(new_val):
 toolbar.pack(side=tkinter.BOTTOM, fill=tkinter.X)
 canvas.get_tk_widget().pack(side=tkinter.TOP, fill=tkinter.BOTH, expand=True)
 
+# Explicitly set focus to canvas for it to receive key press events
+canvas.get_tk_widget().focus_set()
+
 tkinter.mainloop()
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -255,8 +255,6 @@ def filter_destroy(event):
                 CloseEvent("close_event", self)._process()
         filter_destroy_id = root.bind("<Destroy>", filter_destroy, "+")
 
-        self._tkcanvas.focus_set()
-
         self._rubberband_rect_black = None
         self._rubberband_rect_white = None
 
