refactor: convert to mixin

packages/pinball_components/sandbox/lib/common/trace.dart

@@ -18,12 +18,17 @@ extension BodyTrace on BodyComponent {
   }
 }
 
-extension Forge2DGameTrace on Forge2DGame {
-  void traceAllBodies({
+mixin Traceable on Forge2DGame {
+  bool get trace;
+
+  Future<void> traceAllBodies({
     Color color = const Color(0xFFFF0000),
-  }) {
-    children
-        .whereType<BodyComponent>()
-        .forEach((bodyComponent) => bodyComponent.trace());
+  }) async {
+    if (trace) {
+      await ready();
+      children
+          .whereType<BodyComponent>()
+          .forEach((bodyComponent) => bodyComponent.trace());
+    }
   }
 }

packages/pinball_components/sandbox/lib/stories/flipper/flipper_game.dart

@@ -5,10 +5,11 @@ import 'package:pinball_components/pinball_components.dart';
 import 'package:sandbox/common/common.dart';
 import 'package:sandbox/stories/ball/basic_ball_game.dart';
 
-class FlipperGame extends BasicBallGame with KeyboardEvents {
+class FlipperGame extends BasicBallGame with KeyboardEvents, Traceable {
   FlipperGame({
-    required this.trace,
-  }) : super(color: const Color(0xFFFF0000));
+    required bool trace,
+  })  : _trace = trace,
+        super(color: const Color(0xFFFF0000));
 
   static const info = '''
     Shows how a Flipper works.
@@ -17,7 +18,10 @@ class FlipperGame extends BasicBallGame with KeyboardEvents {
     - Tap anywhere on the screen to spawn a ball into the game.
 ''';
 
-  final bool trace;
+  final bool _trace;
+
+  @override
+  bool get trace => _trace;
 
   static const _leftFlipperKeys = [
     LogicalKeyboardKey.arrowLeft,
@@ -47,9 +51,8 @@ class FlipperGame extends BasicBallGame with KeyboardEvents {
       leftFlipper,
       rightFlipper,
     ]);
-    await ready();
 
-    if (trace) traceAllBodies();
+    await traceAllBodies();
   }
 
   @override

packages/pinball_components/sandbox/lib/stories/kicker/kicker_game.dart

@@ -3,10 +3,11 @@ import 'package:pinball_components/pinball_components.dart';
 import 'package:sandbox/common/common.dart';
 import 'package:sandbox/stories/ball/basic_ball_game.dart';
 
-class KickerGame extends BasicBallGame {
+class KickerGame extends BasicBallGame with Traceable {
   KickerGame({
-    required this.trace,
-  }) : super(color: const Color(0xFFFF0000));
+    required bool trace,
+  })  : _trace = trace,
+        super(color: const Color(0xFFFF0000));
 
   static const info = '''
     Shows how Kickers are rendered.
@@ -15,7 +16,10 @@ class KickerGame extends BasicBallGame {
     - Tap anywhere on the screen to spawn a ball into the game.
 ''';
 
-  final bool trace;
+  final bool _trace;
+
+  @override
+  bool get trace => _trace;
 
   @override
   Future<void> onLoad() async {
@@ -30,8 +34,7 @@ class KickerGame extends BasicBallGame {
     final rightKicker = Kicker(side: BoardSide.right)
       ..initialPosition = Vector2(center.x + (Kicker.size.x * 2), center.y);
     await add(rightKicker);
-    await ready();
 
-    if (trace) traceAllBodies();
+    await traceAllBodies();
   }
 }

packages/pinball_components/sandbox/lib/stories/slingshot/slingshot_game.dart

@@ -3,10 +3,11 @@ import 'package:pinball_components/pinball_components.dart';
 import 'package:sandbox/common/common.dart';
 import 'package:sandbox/stories/ball/basic_ball_game.dart';
 
-class SlingshotGame extends BasicBallGame {
+class SlingshotGame extends BasicBallGame with Traceable {
   SlingshotGame({
-    required this.trace,
-  }) : super(color: const Color(0xFFFF0000));
+    required bool trace,
+  })  : _trace = trace,
+        super(color: const Color(0xFFFF0000));
 
   static const info = '''
     Shows how Slingshots are rendered.
@@ -15,17 +16,16 @@ class SlingshotGame extends BasicBallGame {
     - Tap anywhere on the screen to spawn a ball into the game.
 ''';
 
-  final bool trace;
+  final bool _trace;
+
+  @override
+  bool get trace => _trace;
 
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-
     await addFromBlueprint(Slingshots());
-    await ready();
-
     camera.followVector2(Vector2.zero());
-
-    if (trace) traceAllBodies();
+    await traceAllBodies();
   }
 }

packages/pinball_components/sandbox/lib/stories/sparky_bumper/sparky_bumper_game.dart

@@ -5,10 +5,11 @@ import 'package:pinball_components/pinball_components.dart';
 import 'package:sandbox/common/common.dart';
 import 'package:sandbox/stories/ball/basic_ball_game.dart';
 
-class SparkyBumperGame extends BasicBallGame {
+class SparkyBumperGame extends BasicBallGame with Traceable {
   SparkyBumperGame({
-    required this.trace,
-  }) : super(color: const Color(0xFF0000FF));
+    required bool trace,
+  })  : _trace = trace,
+        super(color: const Color(0xFF0000FF));
 
   static const info = '''
     Shows how a SparkyBumper is rendered.
@@ -16,7 +17,10 @@ class SparkyBumperGame extends BasicBallGame {
     Activate the "trace" parameter to overlay the body.
 ''';
 
-  final bool trace;
+  final bool _trace;
+
+  @override
+  bool get trace => _trace;
 
   @override
   Future<void> onLoad() async {
@@ -37,8 +41,7 @@ class SparkyBumperGame extends BasicBallGame {
       sparkyBumperB,
       sparkyBumperC,
     ]);
-    await ready();
 
-    if (trace) traceAllBodies();
+    await traceAllBodies();
   }
 }