const vs final | const vs final in Flutter

In flutter const and final are very commonly used and both are used for different purposes, const value are known at compile-time whereas , final value determined at runtime. Both const and final promote immutability, contributing to safer and more predictable code.

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
//In this we use const and final in same 
  // Here const for compile-time constants
  static const int compileTimeConstant = 42;
  static const String compileTimeString = "Hello, const!";

  // Here final for values determined at runtime
  final int runtimeValue = DateTime.now().second;
  final String runtimeString = "Hello, final!";

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('ResearchThinker: const vs final in Flutter'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
//when we run the program and refresh the values of runtime will change
              Text('Compile-time constant: $compileTimeConstant'),
              Text('Compile-time string: $compileTimeString'),
              SizedBox(height: 20),
              Text('Runtime value: $runtimeValue'),
              Text('Runtime string: $runtimeString'),
            ],
          ),
        ),
      ),
    );
  }
}

Here we execute this program and use web (chrome), so above screenshots related to this program clearly shows that when we refresh the runtime value change and compile value remain same.

compileTimeConstant and compileTimeString are declared with const because their values are known at compile time.

runtimeValue and runtimeString are declared with final because their values are determined at runtime.