How to generate unique id in Dart

In year 2020 you can do UniqueKey(); which is a built in class:

https://api.flutter.dev/flutter/widgets/UniqueKey-class.html

Note

A key that is only equal to itself.

This cannot be created with a const constructor because that implies that all instantiated keys would be the same instance and therefore not be unique.

Besides from uuid, you can also try this to generate small unique keys:

https://pub.dev/packages/nanoid

They even have a collision calculator:

https://zelark.github.io/nano-id-cc/

1. There is a UUID pub package:

http://pub.dartlang.org/packages/uuid

example usage:

import 'package:uuid/uuid.dart';

// Create uuid object
var uuid = Uuid();

// Generate a v1 (time-based) id
uuid.v1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a'

// Generate a v4 (random) id
uuid.v4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'

// Generate a v5 (namespace-name-sha1-based) id
uuid.v5(uuid.NAMESPACE_URL, 'www.google.com'); // -> 'c74a196f-f19d-5ea9-bffd-a2742432fc9c'

2. This src has a dart GUID generator

https://github.com/MikeMitterer/AndroidIconGenerator.DART/blob/445884924/lib/src/model/communication/GUIDGen.dart

I'll not post the function src here directly as there is no apparent licence with it, but example usage is as follows:

final String uuid = GUIDGen.generate();