Deprecate never used resize_callback param to FigureCanvasTk.

anntzer · anntzer · commit f076d3784d10 · 2020-11-27T00:44:34.000+01:00
AFAICT this was present since all the way back in e34a333 but never actually used. The standard way of registering callbacks (either at the Tk level or at the Matplotlib level) seems good enough.
diff --git a/doc/api/next_api_changes/deprecations/19019-AL.rst b/doc/api/next_api_changes/deprecations/19019-AL.rst
@@ -0,0 +1,5 @@
+*resize_callback* parameter to ``FigureCanvasTk``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+This parameter was never used internally and is deprecated.  Tk-level custom
+event handlers for resize events can be added to a ``FigureCanvasTk`` using
+e.g. ``get_tk_widget().bind('<Configure>', ..., True)``.
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -159,6 +159,9 @@ def _on_timer(self):
 class FigureCanvasTk(FigureCanvasBase):
     required_interactive_framework = "tk"
 
+    @cbook._delete_parameter(
+        "3.4", "resize_callback",
+        alternative="get_tk_widget().bind('<Configure>', ..., True)")
     def __init__(self, figure, master=None, resize_callback=None):
         super().__init__(figure)
         self._idle = True
