Dagger2 Multibinding [dagger.android.AndroidInjector.inject(T)] Found a dependency cycle:

Question

I am trying to replicate what ViewModelFactory does for my presenter classes, Here is my Dagger2 Code

public class App extends DaggerApplication { //Support import
    @Override
    protected AndroidInjector<? extends DaggerApplication> applicationInjector() {
        return DaggerAppComponent.builder().create(this);
    }
}


@Documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@MapKey
public @interface PresenterKey {
    Class<? extends PresenterClass> value();
}

    @Module
public abstract class PresenterModule {

    @Binds
    @IntoMap
    @PresenterKey(AuthPresenterImpl.class)
    abstract PresenterClass bindsAuthPresenterImpl(AuthPresenterImpl authViewModel);

    @Binds
    abstract PresenterFactory bindsPresenterFactory(PresenterFactory viewModelFactory);
}


@Singleton
public class PresenterFactory {
    private final Map<Class<? extends PresenterClass>, Provider<PresenterClass>> creators;

    @Inject
    public PresenterFactory(Map<Class<? extends PresenterClass>, Provider<PresenterClass>> creators) {
        this.creators = creators;
    }

    @SuppressWarnings("unchecked")
    public <T extends PresenterClass> T create(Class<T> modelClass) {
        Provider<? extends PresenterClass> creator = creators.get(modelClass);
        if (creator == null) {
            for (Map.Entry<Class<? extends PresenterClass>, Provider<PresenterClass>> entry : creators.entrySet()) {
                if (modelClass.isAssignableFrom(entry.getKey())) {
                    creator = entry.getValue();
                    break;
                }
            }
        }
        if (creator == null) {
            throw new IllegalArgumentException("unknown model class " + modelClass);
        }
        try {
            return (T) creator.get();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

When i try to build i get error as

    import in.silentsudo.authflow.di.modules.DaggerAppComponent;
                                        ^
  symbol:   class DaggerAppComponent
  location: package in.silentsudo.authflow.di.modules
/path/to/project/app/src/main/java/in/silentsudo/authflow/di/modules/AppComponent.java:17: error: [Dagger/BindingCycle] [dagger.android.AndroidInjector.inject(T)] Found a dependency cycle:
public interface AppComponent extends AndroidInjector<AuthFlow> {
       ^
      in.silentsudo.authflow.viewmodels.PresenterFactory is injected at
          in.silentsudo.authflow.di.modules.PresenterModule.bindsPresenterFactory(presenterFactory)
      in.silentsudo.authflow.viewmodels.PresenterFactory is injected at
          in.silentsudo.authflow.AbstractActivity.factory
      in.silentsudo.authflow.auth.AuthActivity is injected at
          dagger.android.AndroidInjector.inject(T)
  component path: in.silentsudo.authflow.di.modules.AppComponent ? in.silentsudo.authflow.di.modules.ActivityModule_BindsAuthActivity.AuthActivitySubcomponent
2 errors

Is there anything wrong i may be doing/anything silly, please help,

EDITED:

Concrete class

public class AuthPresenterImpl extends AbstractPresenter {

    @Inject
    public AuthPresenterImpl(AuthApi api) {

    }
}

score 1 · Answer 1 · answered Aug 22 '18 at 07:40

1

Here is your dependency cycle:

@Binds
@IntoMap
@PresenterKey(PresenterClass.class)
abstract PresenterClass bindsAuthPresenterClass(PresenterClass authViewModel);

You must pass a concrete implementation like such:

@Binds
@IntoMap
@PresenterKey(ConcretePresenterClass.class)
abstract PresenterClass bindsAuthPresenterClass(ConcretePresenterClass authViewModel);

Refer Dagger 2 - Why is this a dependency cycle?

answered Aug 22 '18 at 07:40

Chetan Sachdeva

11
2

Unfortunately it still no working. I am updating with what you have suggested. – silentsudo Aug 22 '18 at 08:59

score 0 · Accepted Answer · answered Aug 22 '18 at 09:32

I managed to solve this, the dependency issue was at this line

@Binds
abstract PresenterFactory bindsPresenterFactory(PresenterFactory viewModelFactory);

Here i needed to return a reference and provide a concrete implementer of that reference. Working changes are below:

public interface PresenterFactory {
    /**
     * Creates a new instance of the given {@code Class}.
     * <p>
     *
     * @param modelClass a {@code Class} whose instance is requested
     * @param <T>        The type parameter for the ViewModel.
     * @return a newly created ViewModel
     */
    @NonNull
    <T extends PresenterClass> T create(@NonNull Class<T> modelClass);
}

Concrete implementer

@Singleton
public class PresenterFactoryImpl implements PresenterFactory {
    private final Map<Class<? extends PresenterClass>, Provider<PresenterClass>> creators;

    @Inject
    public PresenterFactoryImpl(Map<Class<? extends PresenterClass>, Provider<PresenterClass>> creators) {
        this.creators = creators;
    }

    @SuppressWarnings("unchecked")
    @Override
    public <T extends PresenterClass> T create(Class<T> modelClass) {
        Provider<? extends PresenterClass> creator = creators.get(modelClass);
        if (creator == null) {
            for (Map.Entry<Class<? extends PresenterClass>, Provider<PresenterClass>> entry : creators.entrySet()) {
                if (modelClass.isAssignableFrom(entry.getKey())) {
                    creator = entry.getValue();
                    break;
                }
            }
        }
        if (creator == null) {
            throw new IllegalArgumentException("unknown model class " + modelClass);
        }
        try {
            return (T) creator.get();
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }
}

and how to define it in PresenterModule

@Module
public abstract class PresenterModule {

    @Binds
    @IntoMap
    @PresenterKey(AuthPresenterImpl.class)
    abstract PresenterClass bindsAuthPresenterImpl(AuthPresenterImpl authViewModel);

    @Binds
    abstract PresenterFactory bindsPresenterFactory(PresenterFactoryImpl viewModelFactory);
}

Dagger2 Multibinding [dagger.android.AndroidInjector.inject(T)] Found a dependency cycle:

2 Answers2