import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) => MaterialApp(home: MyHomePage());
}

class MyHomePage extends StatelessWidget {
  MyHomePage({Key key}) : super(key: key);
  @override
  Widget build(BuildContext context) => Scaffold(
        floatingActionButton: Builder(
          builder: (context) => FloatingActionButton(
            onPressed: () {
              showBottomSheet(
                  context: context,
                  builder: (context) => SafeArea(
                        child: Container(
                          height: 100,
                          width: 200,
                          color: Colors.red,
                        ),
                      ));
            },
          ),
        ),
      );
}