Sources for blog post "Dependency injection with Dagger 2 - the API"

ActivityScope.java

@Scope
public @interface ActivityScope {
}

AppComponent.java

@Singleton
@Component(
    modules = {
        AppModule.class,
        GithubApiModule.class
    }
)
public interface AppComponent {

    void inject(GithubClientApplication githubClientApplication);

    Application getApplication();

    AnalyticsManager getAnalyticsManager();

    UserManager getUserManager();
}

DaggerApi.java

public @interface Component {
    Class<?>[] modules() default {};
    Class<?>[] dependencies() default {};
}

public @interface Subcomponent {
    Class<?>[] modules() default {};
}

public @interface Module {
    Class<?>[] includes() default {};
}

public @interface Provides {
}

public @interface MapKey {
    boolean unwrapValue() default true;
}

public interface Lazy<T> {
    T get();
}

GithubApiModule.java

@Module
public class GithubApiModule {
    
    @Provides
    @Singleton
    OkHttpClient provideOkHttpClient() {
        OkHttpClient okHttpClient = new OkHttpClient();
        okHttpClient.setConnectTimeout(60 * 1000, TimeUnit.MILLISECONDS);
        okHttpClient.setReadTimeout(60 * 1000, TimeUnit.MILLISECONDS);
        return okHttpClient;
    }

    @Provides
    @Singleton
    RestAdapter provideRestAdapter(Application application, OkHttpClient okHttpClient) {
        RestAdapter.Builder builder = new RestAdapter.Builder();
        builder.setClient(new OkClient(okHttpClient))
               .setEndpoint(application.getString(R.string.endpoint));
        return builder.build();
    }
}

GithubApiModule2.java

@Module
public class GithubApiModule {
    
    //...
    
    @Provides   //This annotation means that method below provides dependency
    @Singleton
    RestAdapter provideRestAdapter(Application application, OkHttpClient okHttpClient) {
        RestAdapter.Builder builder = new RestAdapter.Builder();
        builder.setClient(new OkClient(okHttpClient))
               .setEndpoint(application.getString(R.string.endpoint));
        return builder.build();
    }
}

InjectionMethods.java

SomeType getSomeType();
Provider<SomeType> getSomeTypeProvider();
Lazy<SomeType> getLazySomeType();

JsrApi.java

public @interface Inject {
}

public @interface Scope {
}

public @interface Qualifier {
}

LoginActivity.java

public class LoginActivity extends BaseActivity {

    @Inject
    LoginActivityPresenter presenter;
    
    //...
}

LoginActivityPresenter.java

public class LoginActivityPresenter {
    
    private LoginActivity loginActivity;
    private UserDataStore userDataStore;
    private UserManager userManager;
    
    @Inject
    public LoginActivityPresenter(LoginActivity loginActivity,
                                  UserDataStore userDataStore,
                                  UserManager userManager) {
        this.loginActivity = loginActivity;
        this.userDataStore = userDataStore;
        this.userManager = userManager;
    }
}

LoginActivityPresenter_method.java

public class LoginActivityPresenter {
    
    private LoginActivity loginActivity;
    
    @Inject 
    public LoginActivityPresenter(LoginActivity loginActivity) {
        this.loginActivity = loginActivity;
    }

    @Inject
    public void enableWatches(Watches watches) {
        watches.register(this);    //Watches instance required fully constructed LoginActivityPresenter
    }
}

MapKey_def.java

@MapKey(unwrapValue = true)
@interface TestKey {
    String value();
}

MapKey_dependencies.java

@Provides(type = Type.MAP)
@TestKey("foo")
String provideFooKey() {
    return "foo value";
}

@Provides(type = Type.MAP)
@TestKey("bar")
String provideBarKey() {
    return "bar value";
}

MapKey_usage.java

@Inject
Map<String, String> map;

map.toString() // => „{foo=foo value, bar=bar value}”

ProvisionMethods.java

SomeType getSomeType();
Set<SomeType> getSomeTypes();
@PortNumber int getPortNumber();

Qualifier_injecting.java

@Inject
@GithubRestAdapter
RestAdapter githubRestAdapter;

@Inject
@FacebookRestAdapter
RestAdapter facebookRestAdapter;

Qualifier_naming.java

@Provides
@Singleton
@GithubRestAdapter  //Qualifier
RestAdapter provideRestAdapter() {
    return new RestAdapter.Builder()
        .setEndpoint("https://api.github.com")
        .build();
}

@Provides
@Singleton
@FacebookRestAdapter  //Qualifier
RestAdapter provideRestAdapter() {
    return new RestAdapter.Builder()
        .setEndpoint("https://api.facebook.com")
        .build();
}

SplashActivity.java

public class SplashActivity extends AppCompatActivity {
    
    @Inject
    LoginActivityPresenter presenter;
    @Inject
    AnalyticsManager analyticsManager;
    
    @Override
    protected void onCreate(Bundle bundle) {
        super.onCreate(bundle);
        getAppComponent().inject(this);
    }
}

SplashActivity2.java

public class SplashActivity extends AppCompatActivity {
    
    //...
    
    @Override 
    protected void onCreate(Bundle bundle) {
        super.onCreate(bundle);
        getAppComponent().inject(this);    //Requested depenencies are injected in this moment
    }
}

SplashActivity_MembersInjector.java

//This class is generated automatically by Dagger 2
public final class SplashActivity_MembersInjector implements MembersInjector<SplashActivity> {

    //...

    @Override
    public void injectMembers(SplashActivity splashActivity) {
        if (splashActivity == null) {
            throw new NullPointerException("Cannot inject members into a null reference");
        }
        supertypeInjector.injectMembers(splashActivity);
        splashActivity.presenter = presenterProvider.get();
        splashActivity.analyticsManager = analyticsManagerProvider.get();
    }
}

SplashActivityComponent.java

@ActivityScope
@Component(      
    modules = SplashActivityModule.class,
    dependencies = AppComponent.class
)
public interface SplashActivityComponent {
    SplashActivity inject(SplashActivity splashActivity);

    SplashActivityPresenter presenter();
}

Was just reading your article. I believe injection of activities should happen before the call to super in onCreate(..) and after the call to super in onAttach() of fragments. At least that's what's in the official docs:

Important - Best practices
An Activity injects Dagger in the onCreate method before calling super.
A Fragment injects Dagger in the onAttach method after calling super.