import 'package:flutter/material.dart';

void main() async {
  runApp(
    const MaterialApp(
      title: 'Flutter Demo',
      home: MyApp(),
    ),
  );
}

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

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final TextEditingController controller = TextEditingController(text: 'Collapsed input height');

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: Padding(
          padding: const EdgeInsets.all(8.0),
          child: TextField(
            controller: controller,
            autofocus: true,
            decoration: const InputDecoration.collapsed(
              hintText: 'Hint text',
              filled: true,
              border: UnderlineInputBorder(),
            ),
          ),
        ),
      ),
    );
  }

  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }
}