correct-game-instantiating

added in: 1.6.0

warning

🛠

Pro+

Warns when a game is instantiated in a stateless widget build method.

Instantiating game in a stateless widget build method cases the game to reset every time Flutter rebuilds the widget.

Example

❌ Bad:

class MyGamePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return GameWidget(game: MyFlameGame()); // LINT: Incorrect game instantiation. The game will reset on each rebuild.
  }
}

✅ Good:

class MyGamePage extends StatefulWidget {
  @override
  State<MyGamePage> createState() => _MyGamePageState();
}

class _MyGamePageState extends State<MyGamePage> {

  late final _game = _MyFlameGame();

  @override
  Widget build(BuildContext context) {
    return GameWidget(game: _game);
  }
}

or:

class MyGamePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return GameWidget.controlled(gameFactory: MyFlameGame.new);
  }
}