docs: add an example to ReorderableListView.builder (#79193)
docs: add an example to ReorderableListView.builder.
diff --git a/packages/flutter/lib/src/material/reorderable_list.dart b/packages/flutter/lib/src/material/reorderable_list.dart
index 13f877c..5d93d9d 100644
--- a/packages/flutter/lib/src/material/reorderable_list.dart
+++ b/packages/flutter/lib/src/material/reorderable_list.dart
@@ -121,6 +121,44 @@
/// constructor. Even more efficient, however, is to create the instances
/// on demand using this constructor's `itemBuilder` callback.
///
+ /// This example creates a list using the
+ /// [ReorderableListView.builder] constructor. Using the [IndexedWidgetBuilder], The
+ /// list items are built lazily on demand.
+ /// {@tool dartpad --template=stateful_widget_material}
+ ///
+ /// ```dart
+ /// final List<int> _items = List<int>.generate(50, (int index) => index);
+ ///
+ /// @override
+ /// Widget build(BuildContext context) {
+ /// final ColorScheme colorScheme = Theme.of(context).colorScheme;
+ /// final Color oddItemColor = colorScheme.primary.withOpacity(0.05);
+ /// final Color evenItemColor = colorScheme.primary.withOpacity(0.15);
+ ///
+ /// return ReorderableListView.builder(
+ /// padding: const EdgeInsets.symmetric(horizontal: 40),
+ /// itemCount:_items.length,
+ /// itemBuilder: (BuildContext context, int index) {
+ /// return ListTile(
+ /// key: Key('$index'),
+ /// tileColor: _items[index].isOdd ? oddItemColor : evenItemColor,
+ /// title: Text('Item ${_items[index]}'),
+ /// );
+ /// },
+ /// onReorder: (int oldIndex, int newIndex) {
+ /// setState(() {
+ /// if (oldIndex < newIndex) {
+ /// newIndex -= 1;
+ /// }
+ /// final int item = _items.removeAt(oldIndex);
+ /// _items.insert(newIndex, item);
+ /// });
+ /// },
+ /// );
+ /// }
+ ///
+ /// ```
+ /// {@end-tool}
/// See also:
///
/// * [ReorderableListView], which allows you to build a reorderable
