feat: Add copyWith method on the TextBoxConfig

examples/lib/stories/rendering/text_example.dart

@@ -77,9 +77,9 @@ class TextExample extends FlameGame {
           size: Vector2(200, 150),
           position: Vector2(size.x / 2, size.y / 2 + 100),
           anchor: Anchor.topCenter,
-          boxConfig: TextBoxConfig(
+          boxConfig: const TextBoxConfig(
             timePerChar: 0.005,
-            margins: const EdgeInsets.fromLTRB(10, 10, 10, 10),
+            margins: EdgeInsets.fromLTRB(10, 10, 10, 10),
           ),
         ),
       ],
@@ -138,6 +138,9 @@ class MyTextBox extends TextBoxComponent {
   Future<void> onLoad() {
     paint = Paint();
     bgRect = Rect.fromLTWH(0, 0, width, height);
+    size.addListener(() {
+      bgRect = Rect.fromLTWH(0, 0, width, height);
+    });
 
     paint.color = Colors.white10;
     return super.onLoad();
@@ -152,7 +155,7 @@ class MyTextBox extends TextBoxComponent {
 
 class MyScrollTextBox extends ScrollTextBoxComponent {
   late Paint paint;
-  late Rect bgRect;
+  late Rect backgroundRect;
 
   MyScrollTextBox(
     String text, {
@@ -165,15 +168,15 @@ class MyScrollTextBox extends ScrollTextBoxComponent {
   @override
   FutureOr<void> onLoad() {
     paint = Paint();
-    bgRect = Rect.fromLTWH(0, 0, width, height);
+    backgroundRect = Rect.fromLTWH(0, 0, width, height);
 
     paint.color = Colors.white10;
     return super.onLoad();
   }
 
   @override
   void render(Canvas canvas) {
-    canvas.drawRect(bgRect, paint);
+    canvas.drawRect(backgroundRect, paint);
     super.render(canvas);
   }
 }

packages/flame/lib/src/components/scroll_text_box_component.dart

@@ -48,19 +48,7 @@ class ScrollTextBoxComponent<T extends TextRenderer> extends PositionComponent {
     final marginBottom = boxConfig?.margins.bottom ?? 0;
     final innerMargins = EdgeInsets.fromLTRB(0, marginTop, 0, marginBottom);
 
-    boxConfig ??= TextBoxConfig();
-    boxConfig = TextBoxConfig(
-      timePerChar: boxConfig.timePerChar,
-      dismissDelay: boxConfig.dismissDelay,
-      growingBox: boxConfig.growingBox,
-      maxWidth: size.x,
-      margins: EdgeInsets.fromLTRB(
-        boxConfig.margins.left,
-        0,
-        boxConfig.margins.right,
-        0,
-      ),
-    );
+    boxConfig = (boxConfig ?? const TextBoxConfig()).copyWith(maxWidth: size.x);
 
     _scrollTextBoxComponent = _ScrollTextBoxComponent<T>(
       text: text,
@@ -119,7 +107,7 @@ class _ScrollTextBoxComponent<T extends TextRenderer> extends TextBoxComponent
   }) : super(
           text: text ?? '',
           textRenderer: textRenderer ?? TextPaint(),
-          boxConfig: boxConfig ?? TextBoxConfig(),
+          boxConfig: boxConfig ?? const TextBoxConfig(),
         );
 
   @override

packages/flame/lib/src/components/text_box_component.dart

@@ -37,13 +37,29 @@ class TextBoxConfig {
   /// beginning (both width and height).
   final bool growingBox;
 
-  TextBoxConfig({
+  const TextBoxConfig({
     this.maxWidth = 200.0,
     this.margins = const EdgeInsets.all(8.0),
     this.timePerChar = 0.0,
     this.dismissDelay,
     this.growingBox = false,
   });
+
+  TextBoxConfig copyWith({
+    double? maxWidth,
+    EdgeInsets? margins,
+    double? timePerChar,
+    double? dismissDelay,
+    bool? growingBox,
+  }) {
+    return TextBoxConfig(
+      maxWidth: maxWidth ?? this.maxWidth,
+      margins: margins ?? this.margins,
+      timePerChar: timePerChar ?? this.timePerChar,
+      dismissDelay: dismissDelay ?? this.dismissDelay,
+      growingBox: growingBox ?? this.growingBox,
+    );
+  }
 }
 
 class TextBoxComponent<T extends TextRenderer> extends TextComponent {
@@ -81,7 +97,7 @@ class TextBoxComponent<T extends TextRenderer> extends TextComponent {
     super.children,
     super.priority,
     super.key,
-  })  : _boxConfig = boxConfig ?? TextBoxConfig(),
+  })  : _boxConfig = boxConfig ?? const TextBoxConfig(),
         _fixedSize = size != null,
         align = align ?? Anchor.topLeft,
         pixelRatio = pixelRatio ??

packages/flame/test/components/text_box_component_test.dart

@@ -11,7 +11,7 @@ void main() {
     test('size is properly computed', () {
       final c = TextBoxComponent(
         text: 'The quick brown fox jumps over the lazy dog.',
-        boxConfig: TextBoxConfig(
+        boxConfig: const TextBoxConfig(
           maxWidth: 100.0,
         ),
       );
@@ -23,7 +23,7 @@ void main() {
     test('size is properly computed with new line character', () {
       final c = TextBoxComponent(
         text: 'The quick brown fox \n jumps over the lazy dog.',
-        boxConfig: TextBoxConfig(
+        boxConfig: const TextBoxConfig(
           maxWidth: 100.0,
         ),
       );
@@ -35,7 +35,7 @@ void main() {
     test('lines are properly computed with new line character', () {
       final c = TextBoxComponent(
         text: 'The quick brown fox \n jumps over the lazy dog.',
-        boxConfig: TextBoxConfig(
+        boxConfig: const TextBoxConfig(
           maxWidth: 400.0,
         ),
       );
@@ -51,7 +51,7 @@ void main() {
       (game) async {
         final component = TextBoxComponent(
           text: 'foo bar',
-          boxConfig: TextBoxConfig(
+          boxConfig: const TextBoxConfig(
             dismissDelay: 10.0,
             timePerChar: 1.0,
           ),

packages/flame/test/text/sprite_font_renderer_test.dart

@@ -37,12 +37,12 @@ void main() {
           TextBoxComponent(
             text: textSample,
             textRenderer: await createRenderer(letterSpacing: 1),
-            boxConfig: TextBoxConfig(maxWidth: 800),
+            boxConfig: const TextBoxConfig(maxWidth: 800),
           ),
           TextBoxComponent(
             text: textSample,
             textRenderer: await createRenderer(scale: 2),
-            boxConfig: TextBoxConfig(maxWidth: 800),
+            boxConfig: const TextBoxConfig(maxWidth: 800),
             position: Vector2(0, 100),
           ),
           TextComponent(