Difference between Const and Final in Dart

Let’s find out the difference between const and final keywords in Dart and Flutter

Are const and final in Dart the same?

With my JavaScript/TypeScript background I was already familiar with the const keyword. In Java, you don’t have const, but the equal is final. When I started working with Dart (for Flutter) I was surprised by both of these two keywords available, for me they looked exactly the same. But of course, they are not.

Comparing the keywords

const String personConst = 'Jeroen';
final String personFinal = 'Jeroen';
personConst = 'Bob'; // Not allowed
personFinal = 'Bob'; // Not allowed

In the code above we create a const and a final variable and assign my name to both. You can’t re-assign both of them.

But what is the difference?

final

• A variable with the final keyword will be initialized at runtime and can only be assigned for a single time.
• In a class and function, you can define a final variable.
• For Flutter specific, when the state is updated, everything in the build method will be initialized again. This…