Dagger2.java

//////////////////// APP COMPONENT //////////////////// 
@PerApp
@Component(modules = {AppModule.class, NetworkModule.class, RepoModule.class})
public interface AppComponent {
    ActivityComponent with(ActivityModule activityModule);
}

//////////////////// ACTIVITY COMPONENT //////////////////// 
@PerActivity
@Subcomponent(modules = ActivityModule.class)
public interface ActivityComponent {
    void inject(LoginActivity loginActivity);
    // ...
}

//////////////////// ACTIVITY MODULE //////////////////// 
@Module
public class ActivityModule {
    protected final Activity mActivity;

    public ActivityModule(Activity activity) {
        mActivity = activity;
    }

    @Provides
    @PerActivity
    Activity providesActivity() {
        return mActivity;
    }

    @Provides
    @PerActivity
    @ContextActivity
    Context providesContext() {
        return mActivity;
    }
}

//////////////////// APP MODULE //////////////////// 
@Module
public class AppModule {

    protected final Application mApplication;

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

    @Provides
    @PerApp
    Application providesApplication() {
        return mApplication;
    }

    @Provides
    @ContextApp
    Context providesContext() {
        return mApplication;
    }
}

//////////////////// REPO MODULE //////////////////// 
@Module
public class RepoModule {
    @Provides
    @PerApp
    Prefser providesPrefser(@ContextApp Context context) {
        return new Prefser(context);
    }

    @Provides
    @PerApp
    UserRepo providesUserRepo(Prefser prefser, ApiService apiService) {
        return new UserRepoReal(prefser, apiService);
    }
}


@Module
public class NetworkModule {
    @Provides
    @PerApp
    OkHttpClient providesOkHttpClient() {
        return new OkHttpClient.Builder()
                .build(); 
    }
    
    @Provides
    @PerApp
    Retrofit providesRetrofit(OkHttpClient okHttpClient) {
        return new Retrofit.Builder()
                .baseUrl("...")
                .addConverterFactory(GsonConverterFactory.create(gson))
                .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
                .client(okHttpClient)
                .build();
    }

    @Provides
    @PerApp
    ApiService providesApiService(Retrofit retrofit) {
        return retrofit.create(ApiService.class);
    }
}