toggle_button.dart

import 'package:flutter/material.dart';

class ToggleButton extends TextButton {
  ToggleButton({
    super.key,
    required super.onPressed,
    super.onLongPress,
    super.onHover,
    super.onFocusChange,
    super.style,
    super.focusNode,
    super.autofocus = false,
    super.clipBehavior = Clip.none,
    required this.selected,
    required Widget super.child,
  });

  final bool selected;

  @override
  ButtonStyleButtonState<ToggleButton> createState() => _ToggleButtonState();

}

class _ToggleButtonState extends ButtonStyleButtonState<ToggleButton> {
  @override
  Set<MaterialState> get materialStates {
    return <MaterialState>{
      if (widget.selected) MaterialState.selected,
      ...super.materialStates
    };
  }
}


class Home extends StatefulWidget {
  const Home({ super.key });

  @override
  State<Home> createState() => _HomeState();
}

class _HomeState extends State<Home> {
  bool selected = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ToggleButton(
          selected: selected,
          onPressed: () {
            setState(() { selected = !selected; });
          },
          child: Text('toggle'),
        ),
      ),
    );
  }
}

void main() {
  runApp(MaterialApp(home: Home()));
}


/*


diff --git a/packages/flutter/lib/src/material/button_style_button.dart b/packages/flutter/lib/src/material/button_style_button.dart
index ab48cf499e..0013a7c8fd 100644
--- a/packages/flutter/lib/src/material/button_style_button.dart
+++ b/packages/flutter/lib/src/material/button_style_button.dart
@@ -138,7 +138,7 @@ abstract class ButtonStyleButton extends StatefulWidget {
   bool get enabled => onPressed != null || onLongPress != null;

   @override
-  State<ButtonStyleButton> createState() => _ButtonStyleState();
+  State<ButtonStyleButton> createState() => ButtonStyleButtonState<ButtonStyleButton>();

   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
@@ -191,7 +191,7 @@ abstract class ButtonStyleButton extends StatefulWidget {
 ///  * [TextButton], a simple button without a shadow.
 ///  * [ElevatedButton], a filled button whose material elevates when pressed.
 ///  * [OutlinedButton], similar to [TextButton], but with an outline.
-class _ButtonStyleState extends State<ButtonStyleButton> with MaterialStateMixin, TickerProviderStateMixin {
+class ButtonStyleButtonState<T extends ButtonStyleButton> extends State<T> with MaterialStateMixin, TickerProviderStateMixin {
   AnimationController? _controller;
   double? _elevation;
   Color? _backgroundColor;
@@ -209,7 +209,7 @@ class _ButtonStyleState extends State<ButtonStyleButton> with MaterialStateMixin
   }

   @override
-  void didUpdateWidget(ButtonStyleButton oldWidget) {
+  void didUpdateWidget(T oldWidget) {
     super.didUpdateWidget(oldWidget);
     setMaterialState(MaterialState.disabled, !widget.enabled);
     // If the button is disabled while a press gesture is currently ongoing,


*/