MultiDexApplication does not implement HasActivityInjector

I use New Android Injector with Dagger 2 by https://medium.com/@iammert/new-android-injector-with-dagger-2-part-1-8baa60152abe

Before MultiDex support App has worked.
I have added multidex support to app/build.gradle and AndroidManifest.xml.
After MultiDex support i have got error logcat by instaling on device

FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.eusecom.samfantozzi/com.eusecom.samfantozzi.Detail2Activity}: java.lang.RuntimeException: android.support.multidex.MultiDexApplication does not implement dagger.android.HasActivityInjector
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2295)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
at android.app.ActivityThread.access$700(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.RuntimeException: android.support.multidex.MultiDexApplication does not implement dagger.android.HasActivityInjector
at dagger.android.AndroidInjection.inject(AndroidInjection.java:48)
at com.eusecom.samfantozzi.Detail2Activity.onCreate(Detail2Activity.java:19)
at android.app.Activity.performCreate(Activity.java:5372)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2257)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349) 
at android.app.ActivityThread.access$700(ActivityThread.java:159) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:137) 
at android.app.ActivityThread.main(ActivityThread.java:5419) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:525) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003) 
at dalvik.system.NativeStart.main(Native Method) 

public class SamfantozziApp extends MultiDexApplication implements HasActivityInjector {



@Inject

DispatchingAndroidInjector<Activity> activityDispatchingAndroidInjector;



public RxBus _rxBus;



@NonNull

private DatabaseReference mDatabaseReference;



@Override

public void onCreate() {

    super.onCreate();



    if (LeakCanary.isInAnalyzerProcess(this)) {

        // This process is dedicated to LeakCanary for heap analysis.

        // You should not init your app in this process.

        return;

    }

    LeakCanary.install(this);



    mDatabaseReference = FirebaseDatabase.getInstance().getReference();



    DaggerAppComponent

            .builder()

            .application(this)

            .build()

            .inject(this);



}



@Override

public DispatchingAndroidInjector<Activity> activityInjector() {

    return activityDispatchingAndroidInjector;

}









@NonNull

public ISchedulerProvider getSchedulerProvider() {

    return SchedulerProvider.getInstance();

}



@NonNull

public DatabaseReference getDatabaseFirebaseReference() {

    return mDatabaseReference;

}





public RxBus getRxBusSingleton() {

    if (_rxBus == null) {

        _rxBus = new RxBus();

    }

    return _rxBus;

}



private final DemoComponent dgaeacomponent = createDgAeaComponent();



protected DemoComponent createDgAeaComponent() {

    return DaggerDemoComponent.builder()

            .applicationModule(new ApplicationModule(this))

            .build();

}



public DemoComponent dgaeacomponent() {

    return dgaeacomponent;

    }



}