Dagger 2 - Why is this a dependency cycle?

Question

I'm trying to inject the application's Context into 2 other objects, an AuthManager and an ApiClient.

Both of them depends on said context, and the ApiClient depends on the AuthManager. Why is this a dependency cycle, if Context doesn't have a reference to the others 2? can this be solved?

EDIT: here is some code

@Module
public class AppModule {

    private final Application application;

    public AppModule(Application application) {
        this.application = application;
    }

    @Provides @Singleton
    Context provideApplicationContext() {
         return this.application;
    }
}


@Module
public class NetworkModule {

    @Provides @Singleton
    public AuthManager providesAuthManager(AuthManager manager) {
        return manager;
    }

    @Provides @Singleton
    public ApiClient providesApiClient(ApiClientFactory factory) {
        return factory.create();
    }
}

@Singleton
@Component(modules = {AppModule.class, NetworkModule.class})
public interface ApplicationComponent {
    void inject(BaseActivity activity);

    // Exported for child-components
    Context context();
    ApiClient apiClient();
    AuthManager authManager();
}

score 86 · Accepted Answer · answered Sep 23 '15 at 21:30

86

@Provides @Singleton
public AuthManager providesAuthManager(AuthManager manager) {
    return manager;
}

Your providesAuthManager method which provides an AuthManager depends on an AuthManager.

There's your cycle :)

answered Sep 23 '15 at 21:30

nhaarman

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It helps to add any error messages you get to the question. In this case, you've interpreted the error message the wrong way, making it harder for us to help :) – nhaarman Sep 23 '15 at 21:31
I see. It seems I misunderstood the coffee maker example, as I thougt by placing the `AuthManager` as a local param, dagger would auto-inject to it. Seems like the right way is to set the `Context` as the local param. Thanks :) – Christopher Francisco Sep 23 '15 at 23:02
1

This answer prompted me to double check a provides method and saved me hours of effort tracking down something caused by a simple typo. Thanks! – user3265561 Jun 24 '16 at 10:04
I think what you are looking for is @Bind – Derek Zhu Apr 10 '18 at 00:37

score 1 · Answer 2 · edited Dec 31 '17 at 13:30

1

Remove the providesAuthManager method and add @Inject in your AuthManager Constructor.

edited Dec 31 '17 at 13:30

peacetype

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answered Dec 31 '17 at 05:07

Yz_me

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This lead to other error: "...cannot be provided without @Provide annotated-method" – nhoxbypass Jan 07 '18 at 18:50

Dagger 2 - Why is this a dependency cycle?

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