Flutter Class vs Function Widget

main.dart

// Open console to view rebuild triggered

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(context) {
    return MaterialApp(
      home: Home(),
    );
  }
}

class Home extends StatefulWidget {
  @override
  State<Home> createState() => _HomeState();
}

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

  Widget _buildTile(
    String title,
  ) {
    print('$title function rebuilt!');
    return InkWell(
      onTap: () {},
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: 10.0),
        child: Row(
          children: [
            Expanded(
              child: Text(title),
            ),
          ],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            _buildTile('AAAAA'),
            _buildTile('BBBBB'),
            const _BuildTile('AAAAA'),
            const _BuildTile('BBBBB'),
            TextButton(
              child: const Text('Trigger setstate'),
              onPressed: () {
                setState(() {});
              },
            ),
          ],
        ),
      ),
    );
  }
}

class _BuildTile extends StatelessWidget {
  final String title;
  const _BuildTile(this.title);

  @override
  Widget build(BuildContext context) {
    print('$title widget rebuilt!');
    return InkWell(
      onTap: () {},
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: 10.0),
        child: Row(
          children: [
            Expanded(
              child: Text(title),
            ),
          ],
        ),
      ),
    );
  }
}