AdoptAWidget - Update ActionListener with an example (#69717)
Adds an example to the docs for ActionListener.
diff --git a/packages/flutter/lib/src/widgets/actions.dart b/packages/flutter/lib/src/widgets/actions.dart
index 3460a8b..24974b5 100644
--- a/packages/flutter/lib/src/widgets/actions.dart
+++ b/packages/flutter/lib/src/widgets/actions.dart
@@ -241,6 +241,102 @@
/// If you listen to an [Action] widget in a widget hierarchy, you should use
/// this widget. If you are using an [Action] outside of a widget context, then
/// you must call removeListener yourself.
+///
+/// {@tool dartpad --template=stateful_widget_scaffold_center}
+/// This example shows how ActionListener handles adding and removing of
+/// the [listener] in the widget lifecycle.
+///
+/// ```dart preamble
+/// class ActionListenerExample extends StatefulWidget {
+/// @override
+/// _ActionListenerExampleState createState() => _ActionListenerExampleState();
+/// }
+///
+/// class _ActionListenerExampleState extends State<ActionListenerExample> {
+/// bool _on = false;
+/// late final MyAction _myAction;
+///
+/// @override
+/// void initState() {
+/// super.initState();
+/// _myAction = MyAction();
+/// }
+///
+/// void _toggleState() {
+/// setState(() {
+/// _on = !_on;
+/// });
+/// }
+///
+/// @override
+/// Widget build(BuildContext context) {
+/// return Row(
+/// crossAxisAlignment: CrossAxisAlignment.center,
+/// mainAxisAlignment: MainAxisAlignment.center,
+/// children: <Widget>[
+/// Padding(
+/// padding: const EdgeInsets.all(8.0),
+/// child: OutlinedButton(
+/// onPressed: _toggleState,
+/// child: Text(_on ? 'Disable' : 'Enable'),
+/// ),
+/// ),
+/// _on
+/// ? Padding(
+/// padding: const EdgeInsets.all(8.0),
+/// child: ActionListener(
+/// listener: (Action<Intent> action) {
+/// if (action.intentType == MyIntent) {
+/// ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+/// content: const Text('Action Listener Called'),
+/// ));
+/// }
+/// },
+/// action: _myAction,
+/// child: ElevatedButton(
+/// onPressed: () =>
+/// ActionDispatcher().invokeAction(_myAction, MyIntent()),
+/// child: const Text('Call Action Listener'),
+/// ),
+/// ),
+/// )
+/// : Container(),
+/// ],
+/// );
+/// }
+/// }
+///
+/// class MyAction extends Action<MyIntent> {
+/// @override
+/// void addActionListener(listener) {
+/// super.addActionListener(listener);
+/// print('Action Listener was added');
+/// }
+///
+/// @override
+/// void removeActionListener(listener) {
+/// super.removeActionListener(listener);
+/// print('Action Listener was removed');
+/// }
+///
+/// @override
+/// void invoke(covariant MyIntent intent) {
+/// notifyActionListeners();
+/// }
+/// }
+///
+/// class MyIntent extends Intent {
+/// const MyIntent();
+/// }
+/// ```
+///
+/// ```dart
+/// Widget build(BuildContext context) {
+/// return ActionListenerExample();
+/// }
+/// ```
+/// {@end-tool}
+///
@immutable
class ActionListener extends StatefulWidget {
/// Create a const [ActionListener].
