import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  double fabSize = 40; // It breaks on app open if this is 0

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ElevatedButton(
          onPressed: () {
            setState(() {
              fabSize = 0;
            });
          },
          child: Text("Resize FAB"),
        ),
      ),
      floatingActionButton: Material(
        // Doesn't fail if elevation is 0
        elevation: 1,
        child: SizedBox(
          width: fabSize,
          height: fabSize,
          child: Icon(Icons.abc),
        ),
      ),
    );
  }
}