Dagger2 Error: Module Must Be Set

Question

I was trying to do SubScoping in Dagger2. However, I am not able to figure out this compilation error:-> ...MyApplicationModule must be set which happens in my LogInFragment. If someone will try to throw some light on this error. I would really be glad.

This is MyApplication Class:

public class MyApplication extends Application {

    @Override
    public void onCreate() {
        super.onCreate();
        MyInjector.initialize(this);
    }
}

This is MyInjector Class:

public enum MyInjector {
    INSTANCE;

    MyApplicationComponent myApplicationComponent;


    private MyInjector() {
    }

    public static void initialize(MyApplication myApplication) {

        MyApplicationComponent myApplicationComponent = DaggerMyApplicationComponent.builder()
                .myApplicationModule(new MyApplicationModule(myApplication))
                .build();
        INSTANCE.myApplicationComponent = myApplicationComponent;
    }

    public static MyApplicationComponent get() {
        return INSTANCE.myApplicationComponent;
    }

}

This is MyApplicationComponent Class:

@Component (modules = {MyApplicationModule.class}) 
public interface MyApplicationComponent { 

}

This is MyApplicationModule Class

@Module
public class MyApplicationModule {

    private final MyApplication myApplication;

    public MyApplicationModule(MyApplication myApplication) {
        this.myApplication = myApplication;
    }

    @Singleton
    @Provides
    SharedPreferences providesSharedPreferences(Context context) {
        return context.getSharedPreferences("My_Pref", Context.MODE_PRIVATE);
    }

    @Singleton
    @Provides
    public Context providesMyApplicationContext() {
        return this.myApplication.getApplicationContext();
    }

    @Singleton
    @Provides
    public LocationManager providesLocationService(Context context) {
        return (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
    }

    @Singleton
    @Provides
    public MyDatabaseManager providesMyDatabaseManager(Context context) {
        return MyDatabaseManager.getInstance(context);
    }

    @Singleton
    @Provides
    public AccountSystemModel providesAccountSystemModel(Context context) {
        return MyDatabaseManager.getInstance(context);
    }

    @Singleton
    @Provides
    public MyApplication providesMyApplication(){
        return this.myApplication;
    }

}

This is where I am trying to Subscope

This is MyLogIn Component Class

@Singleton
@Component(modules = {MyApplicationModule.class}, dependencies = {MyApplicationComponent.class})
public interface LogInComponent {
    LogInPresenter signInPresenter();
}

This is where the Compilation Error happens

This is MyLogInActivityFragment

@Override protected void injectDependencies() {
   logInComponent = DaggerLogInComponent.builder()
                    .myApplicationComponent(MyInjector.get())
                    .build();
}

Answer 1

Your LogInComponent depends on MyApplicationComponent which contains MyApplicationModule. You shouldn't be declaring this same module in the LogInComponent too. Remove it and it will compile.

---

Also, make sure you expose dependencies you need in the LogInComponent from MyApplicationComponent by adding them to the component interface like so:

@Component (modules = {MyApplicationModule.class}) 
public interface MyApplicationComponent { 
    Context context();
    SharedPreferences sharedPreferences();
    // ...
}

---

Another tip – if you need all dependencies from the MyApplicationComponent you might want to read about subcomponents.

Answer 2

The error can be caused by an abstract class module. Modules can't be used by Dagger if they are abstract classes.