Dart Generic Enums Example

rpg_class_preview_app.dart

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

abstract class ClassPreviewConfig { 
  final String name;
  final String icon;
  final String description;
  
  const ClassPreviewConfig(this.name, this.icon, this.description);
}

class WarriorPreviewConfig extends ClassPreviewConfig { 
  const WarriorPreviewConfig(super.name, super.icon, super.description);
}

class RangerPreviewConfig extends ClassPreviewConfig { 
  const RangerPreviewConfig(super.name, super.icon, super.description);
}

class ThiefPreviewConfig extends ClassPreviewConfig { 
  const ThiefPreviewConfig(super.name, super.icon, super.description);
}

class ClericPreviewConfig extends ClassPreviewConfig { 
  const ClericPreviewConfig(super.name, super.icon, super.description);
}

enum ClassPreview<T extends ClassPreviewConfig> {
  warrior(WarriorPreviewConfig('warrior', 'warrior.png', 'smacky mcmuscles')),
  ranger(RangerPreviewConfig('ranger', 'ranger.png', 'tracky mcpewpew')),
  thief(ThiefPreviewConfig('thief', 'thief.png', 'stabby mcklepto')),
  cleric(ClericPreviewConfig('cleric', 'cleric.png', 'uptight mchealy'));
  
  final T config;
  
  const ClassPreview(this.config);
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const HomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class HomePage extends StatelessWidget {
  final String title;

  const HomePage({
    Key? key,
    required this.title,
  }) : super(key: key);
  
  Widget buildClassPreviewButton(BuildContext context, ClassPreview classPreview) {
    return Padding(
      padding: const EdgeInsets.only(top: 8),
      child: ElevatedButton(
        child: Text(classPreview.config.name),
        onPressed: () => Navigator.of(context).push(
          MaterialPageRoute(
            builder: (cxt) => ClassPreviewPage(classPreview),
          ),
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Home'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Text('Select a class:'),
            const SizedBox(height: 12),
            buildClassPreviewButton(context, ClassPreview.warrior),
            buildClassPreviewButton(context, ClassPreview.ranger),
            buildClassPreviewButton(context, ClassPreview.thief),
            buildClassPreviewButton(context, ClassPreview.cleric),
          ],
        ),
      ),
    );
  }
}

class ClassPreviewPage extends StatelessWidget {
  final ClassPreview classPreview;
  
  const ClassPreviewPage(this.classPreview);
  
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(classPreview.config.name),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text(classPreview.config.name),
            Text(classPreview.config.icon),
            Text(classPreview.config.description),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.arrow_left),
        onPressed: () => Navigator.of(context).pop(), 
      ),
    );
  }
}