feat: Added PeriodicScope.

packages/katana_ui/lib/katana_ui.dart

@@ -26,3 +26,4 @@ part 'ui/indent.dart';
 part 'ui/card_tile.dart';
 part 'ui/label.dart';
 part 'ui/line_tile.dart';
+part 'ui/periodic_scope.dart';

packages/katana_ui/lib/ui/periodic_scope.dart

@@ -0,0 +1,61 @@
+part of katana_ui;
+
+/// This widget repeatedly redraws at regular intervals.
+///
+/// Draw [builder] at every interval of [duration].
+///
+/// 一定時間ごとに繰り返して再描画するウィジェットです。
+///
+/// [duration]の間隔ごとに[builder]を描画します。
+class PeriodicScope extends StatefulWidget {
+  /// This widget repeatedly redraws at regular intervals.
+  ///
+  /// Draw [builder] at every interval of [duration].
+  ///
+  /// 一定時間ごとに繰り返して再描画するウィジェットです。
+  ///
+  /// [duration]の間隔ごとに[builder]を描画します。
+  const PeriodicScope({
+    super.key,
+    required this.duration,
+    required this.builder,
+  });
+
+  /// Interval between drawings.
+  ///
+  /// 描画を行う間隔。
+  final Duration duration;
+
+  /// Builder for drawing.
+  ///
+  /// 描画を行うためのビルダー。
+  final Widget Function(BuildContext context, DateTime now) builder;
+
+  @override
+  State<StatefulWidget> createState() => _PeriodicScopeState();
+}
+
+class _PeriodicScopeState extends State<PeriodicScope> {
+  Timer? _timer;
+
+  @override
+  void initState() {
+    super.initState();
+    _timer = Timer.periodic(widget.duration, (timer) {
+      setState(() {});
+    });
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    _timer?.cancel();
+    _timer = null;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final now = DateTime.now();
+    return widget.builder.call(context, now);
+  }
+}

packages/katana_ui/pubspec.lock

@@ -204,7 +204,7 @@ packages:
       path: "../katana"
       relative: true
     source: path
-    version: "2.3.2"
+    version: "2.3.3"
   lints:
     dependency: transitive
     description: