Merge pull request #18226 from QuLogic/widget-cbs

timhoffm · web-flow · commit a1159a4bb967 · 2020-08-18T17:38:50.000+02:00
Use CallbackRegistry in Widgets and some related cleanup
diff --git a/doc/api/next_api_changes/behavior/18226-ES.rst b/doc/api/next_api_changes/behavior/18226-ES.rst
@@ -0,0 +1,10 @@
+Widgets use ``CallbackRegistry`` to save callbacks
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`.Widget`\s with event observers now use a `.CallbackRegistry` for storing
+callbacks. This is consistent with canvas event callbacks, and fixes some bugs
+in widget callback handling.
+
+Due to this change, callback methods are now stored as weak references, which
+means you must keep a reference to the associated object. Otherwise it may be
+garbage collected.
diff --git a/doc/api/next_api_changes/deprecations/18226-ES.rst b/doc/api/next_api_changes/deprecations/18226-ES.rst
@@ -0,0 +1,12 @@
+Widget class internals
+~~~~~~~~~~~~~~~~~~~~~~
+
+Several `.widgets.Widget` class internals have been privatized and deprecated:
+
+* ``AxesWidget.cids``
+* ``Button.cnt`` and ``Button.observers``
+* ``CheckButtons.cnt`` and ``CheckButtons.observers``
+* ``RadioButtons.cnt`` and ``RadioButtons.observers``
+* ``Slider.cnt`` and ``Slider.observers``
+* ``TextBox.cnt``, ``TextBox.change_observers`` and
+  ``TextBox.submit_observers``
diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
