All Devices Aspect Ratio

aspect_ratio.dart

import 'package:flutter/material.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Container(
          color: Colors.blueGrey[200],
          child: Center(
            child: FractionallySizedBox(
              widthFactor: 0.8,
              heightFactor: 0.4,
              child: Container(
                  alignment: Alignment.center,
                  color: Colors.orange,
                  child: _aspectRatio()),
            ),
          ),
        ),
      ),
    );
  }

  Widget _aspectRatio() {
    return AspectRatio(
      aspectRatio: 16 / 9,
      child: Container(
        alignment: Alignment.center,
        color: Colors.green,
        child: const Text(
          '16:9 Aspect Ratio',
          style: TextStyle(
            color: Colors.white,
            fontSize: 24,
          ),
        ),
      ),
    );
  }
}