MultiToken class - di library

A token representing multiple values of T for dependency injection.

const usPresidents = const MultiToken<String>('usPresidents');

@Component(
  selector: 'presidents-list',
  providers: const [
    const ValueProvider.forToken(usPresidents, 'George Washington'),
    const ValueProvider.forToken(usPresidents, 'Abraham Lincoln'),
  ],
)
class PresidentsListComponent {
  // Will be ['George Washington', 'Abraham Lincoln'].
  final List<String> items;

  PresidentsListComponent(@Inject(usPresidents) this.items);
}

The type T is not required, but is recommended, otherwise it is dynamic.

The only positional argument, uniqueName, is used to determine uniqueness of the token. That is, const MultiToken('SECRETS') is identical to const MultiToken('SECRETS') in another library or package.

You may also sub-class MultiToken to create a "more unique" token:

class UsPresidents extends MultiToken<String> {
  const UsPresidents();
}

const usPresidents = const UsPresidents();

@Component(
  selector: 'presidents-list',
  providers: const [
    const ValueProvider.forToken(usPresidents, 'George Washington'),
    const ValueProvider.forToken(usPresidents, 'Abraham Lincoln'),
  ],
)
class PresidentsListComponent {
  // Will be ['George Washington', 'Abraham Lincoln'].
  final List<String> items;

  PresidentsListComponent(@Inject(usPresidents) this.items);
}

This is is the preferred mechanism for configuring multiple bound values to a single token, and will replace Provider(..., multi: true) and other variations of the multi: true APIs.

WARNING: It is not supported to create a non-const instance of this class or sub-types of this class. Instances should only be created or referenced using the const operator.

di library

MultiToken<T> class

Constructors

Properties

Methods

Operators