Evaluating flags in non-UI code

The OpenFeatureClient class can be used to evaluate flags in non-UI code. Let's head to counter_page.dart where we have incrementCounter method that is responsible for incrementing the counter. Here, we'll make it so that the increment factor is decided based on the email of user.

Update the method as given below:

Future<void> _incrementCounter() async {
  final client = OpenFeature.instance.getClient();
  final increment = await client.getNumberValue(
    key: 'increment',
    defaultValue: 1,
    context: EvaluationContext({'email': widget.email ?? ''}),

  _counter += increment as int;
  setState(() {});

The evaluation process is similar to that of previous step. For instance, if you login with email user@feature.flag then the flag will be resolved with "double" variant. Thus, will increment the counter by 2 in each tap of the FAB.