fragment cannot be provided without an @Provides-annotated method. Kotlin

Question

My Application class

class MyApp : Application(), HasActivityInjector {

@Inject
lateinit var activityInjector: DispatchingAndroidInjector<Activity>

/*@Inject
lateinit var fragmentInjector: DispatchingAndroidInjector<Fragment>*/

override fun onCreate() {
    super.onCreate()
    DaggerAppComponent.builder().application(this).build().inject(this)
}

override fun activityInjector(): AndroidInjector<Activity> = 
activityInjector
//override fun supportFragmentInjector(): AndroidSupportInjection<Fragment> 
= fragmentInjector
}

App Component

@Singleton
@Component(modules = arrayOf(AndroidInjectionModule::class, 
AppModule::class, BuilderModule::class))
interface AppComponent {
@Component.Builder
interface Builder {
    @BindsInstance
    fun application(application: Application): Builder

    fun build(): AppComponent
}

fun inject(app: MyApp)

}

App Module

@Module
class AppModule {
   @Provides
   @Singleton
   fun provideUtil(application: Application): Utils = Utils(application)
}

Builder Module

@Module
abstract class BuilderModule {
   @ContributesAndroidInjector
   abstract fun contributeMainActivity(): MainActivity

   @ContributesAndroidInjector
   abstract fun contributeHomeFragment(): HomeFragment
}

Main Activity

class MainActivity : AppCompatActivity(), HasSupportFragmentInjector {

   @Inject
   lateinit var fragmentInjector: DispatchingAndroidInjector<Fragment>

   override fun supportFragmentInjector(): AndroidInjector<Fragment> = 
   fragmentInjector


   override fun onCreate(savedInstanceState: Bundle?) {
       AndroidInjection.inject(this); // Call before super!
       super.onCreate(savedInstanceState)
       setContentView(R.layout.activity_main)

       replaceFragment(HomeFragment())
    }

    fun replaceFragment(fragment: Fragment) {
        val transaction = supportFragmentManager.beginTransaction()
        transaction.replace(R.id.frameContainer, fragment)
        transaction.addToBackStack(null)
        transaction.commit()
    }
}

Home Fragment

class HomeFragment : Fragment() {

   @Inject
   lateinit var utils: Utils

   override fun onAttach(context: Context?) {
      AndroidSupportInjection.inject(this) // Providing the dependency
      super.onAttach(context)
   }

   override fun onCreateView(inflater: LayoutInflater, container: 
   ViewGroup?, savedInstanceState: Bundle?): View? {
     // Inflate the layout for this fragment
     return inflater.inflate(R.layout.fragment_home, container, false)
   }

   override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
      super.onViewCreated(view, savedInstanceState)
      utils.toaster("Injected")
   }

I am getting this error D:\Workspace\DaggerKotlin\app\build\tmp\kapt3\stubs\debug\com\cvsingh\daggerkotlin\di\AppComponent.java:8: error: [Dagger/MissingBinding] [dagger.android.AndroidInjector.inject(T)] java.util.Map>> cannot be provided without an @Provides-annotated method. public abstract interface AppComponent { ^ java.util.Map>> is injected at dagger.android.DispatchingAndroidInjector.(…, injectorFactoriesWithStringKeys) dagger.android.DispatchingAndroidInjector is injected at com.cvsingh.daggerkotlin.ui.MainActivity.fragmentInjector com.cvsingh.daggerkotlin.ui.MainActivity is injected at dagger.android.AndroidInjector.inject(T) component path: com.cvsingh.daggerkotlin.di.AppComponent ? com.cvsingh.daggerkotlin.di.BuilderModule_ContributeMainActivity.MainActivitySubcomponent

}

Answer 1

You're doing it wrong with your MyApp class, you should use DaggerApplication to simplify you dagger integration :

class MyApp : DaggerApplication() {
    private val applicationInjector = DaggerApplicationComponent.builder()
        .application(this)
        .build()

    override fun applicationInjector() = applicationInjector
}

And for your information you can simplify the same way your activites and fragments using DaggerAppCompatActivity and DaggerFragment

for example your activity could be :

class MainActivity : DaggerAppCompatActivity(){

   override fun onCreate(savedInstanceState: Bundle?) {
       super.onCreate(savedInstanceState)
       setContentView(R.layout.activity_main)

       replaceFragment(HomeFragment())
    }

    fun replaceFragment(fragment: Fragment) {
        val transaction = supportFragmentManager.beginTransaction()
        transaction.replace(R.id.frameContainer, fragment)
        transaction.addToBackStack(null)
        transaction.commit()
    }
}

If you don't want to use DaggerApplication, DaggerAppCompatActivity, etc.. (sometimes you need to extends from another class) then simply copy paste code from DaggerApplication, DaggerAppCompatActivity, etc in your class