refactor: defined FlutterSIgnPostSprite

packages/pinball_components/lib/src/components/flutter_sign_post.dart

@@ -6,28 +6,13 @@ import 'package:pinball_components/pinball_components.dart';
 /// {@template flutter_sign_post}
 /// A sign, found in the Flutter Forest.
 /// {@endtemplate}
-// TODO(alestiago): Revisit doc comment if FlutterForest is moved to package.
 class FlutterSignPost extends BodyComponent with InitialPosition {
-  Future<void> _loadSprite() async {
-    final sprite = await gameRef.loadSprite(
-      Assets.images.flutterSignPost.keyName,
-    );
-    final spriteComponent = SpriteComponent(
-      sprite: sprite,
-      size: sprite.originalSize / 10,
-      anchor: Anchor.bottomCenter,
-      position: Vector2(0.65, 0.45),
-    );
-    await add(spriteComponent);
-  }
-
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-    paint = Paint()
-      ..color = Colors.blue.withOpacity(0.5)
-      ..style = PaintingStyle.fill;
-    await _loadSprite();
+    renderBody = false;
+
+    await add(_FlutterSignPostSprite());
   }
 
   @override
@@ -39,3 +24,18 @@ class FlutterSignPost extends BodyComponent with InitialPosition {
     return world.createBody(bodyDef)..createFixture(fixtureDef);
   }
 }
+
+class _FlutterSignPostSprite extends SpriteComponent with HasGameRef {
+  @override
+  Future<void> onLoad() async {
+    await super.onLoad();
+
+    final sprite = await gameRef.loadSprite(
+      Assets.images.flutterSignPost.keyName,
+    );
+    this.sprite = sprite;
+    size = sprite.originalSize / 10;
+    anchor = Anchor.bottomCenter;
+    position = Vector2(0.65, 0.45);
+  }
+}