Controlling State from outside of a StatefulWidget

Question

I\'m trying to understand the best practice for controlling a StatefulWidget\'s state outside of that Widgets State.

I have the following interface defined.

<

Answer 1

You can expose the state's widget with a static method, a few of the flutter examples do it this way and I've started using it as well:

class StartupPage extends StatefulWidget {
  static _StartupPageState of(BuildContext context) => context.ancestorStateOfType(const TypeMatcher<_StartupPageState>());

  @override
  _StartupPageState createState() => new _StartupPageState();
}

class _StartupPageState extends State {
  ...
}

You can then access the state by calling StartupPage.of(context).doSomething();.

The caveat here is that you need to have a BuildContext with that page somewhere in its tree.