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I have the following problem: I started to study Dagger 2 and trying to add injections to my App class. Here's the code of my App class:

class TraktTvApp : Application(), HasActivityInjector {
    @Inject
    lateinit var androidInjector: AndroidInjector<Activity>
    override fun activityInjector(): AndroidInjector<Activity>? = androidInjector
    override fun onCreate() {
        super.onCreate()
        appContext = applicationContext
        instance = this
        initStetho()
        initFabric()
        DaggerAppComponent
                .builder()
                .application(this)
                .build()
                .inject(this)
        FirebaseInstanceId.getInstance().instanceId
                .addOnCompleteListener(OnCompleteListener { task ->
                    if (!task.isSuccessful) {
                        return@OnCompleteListener
                    val token = task.result?.token
    private fun initFabric() {
        Fabric.with(this, Crashlytics(), CrashlyticsNdk())
    private fun initStetho() {
        if (BuildConfig.DEBUG) {
            Stetho.initializeWithDefaults(this)
    companion object {
        lateinit var instance: TraktTvApp
        lateinit var appContext: Context
In this class I have appContext as Property and I am trying to replace it with injection. For this purpose I added this lines     
DaggerAppComponent
            .builder()
            .application(this)
            .build()
            .inject(this)
When I build my App everything was ok, but when I added
    @Inject
    lateinit var androidInjector: AndroidInjector<Activity>
    override fun activityInjector(): AndroidInjector<Activity>? = androidInjector
And tried to build I got this error:
public abstract interface AppComponent {
      dagger.android.AndroidInjector<android.app.Activity> is injected at
          com.mikhailovskii.trakttv.TraktTvApp.androidInjector
      com.mikhailovskii.trakttv.TraktTvApp is injected at
          com.mikhailovskii.trakttv.di.AppComponent.inject(com.mikhailovskii.trakttv.TraktTvApp)
I have already seen possible solutions, but none of them helped me. Here's the code of my AppModule:
@Module
class AppModule {
    @Singleton
    @Provides
    fun provideContext(application: TraktTvApp): Context {
        return application.applicationContext
And here's AppComponent:
@Singleton
@Component(
        modules = [
            AndroidSupportInjectionModule::class,
            AppModule::class
interface AppComponent {
    @Component.Builder
    interface Builder {
        @BindsInstance
        fun application(application: TraktTvApp): Builder
        fun build():AppComponent
    fun inject(application: TraktTvApp)
So, what's the problem and how can I solve it?
You do not need to add AndroidInjector manually. You can use Dagger base classes so Dagger will handle it for you
You should extend your Application class from DaggerApplication
 class MyApp: DaggerApplication() {
     * Returns the injector
    override fun applicationInjector(): AndroidInjector<out DaggerApplication> {
        val appComponent = DaggerAppComponent.builder().application(this).build()
        appComponent.inject(this)
        return appComponent
Also your Main Component extends AndroidInjector
 * The main component that holds and services all modules within its builder.
@Singleton
@Component(modules = [AndroidSupportInjectionModule::class])
interface AppComponent : AndroidInjector<MyApp> {
     * A {@see [Component.Builder]} that initializes necessary implementations
    @Component.Builder
    interface Builder {
        @BindsInstance
        fun application(application : Application) : Builder
        fun build() : AppComponent
If you want to use Context, you can add it your AppModule
@Module
class AppModule {
    @Singleton
    @Provides
    fun provideContext(application: Application): Context {
        return application.applicationContext
                Yes, thanks a lot, but can you explain me also what way should I get the context now? Before I did in in the following way: TraktTvApp.appContext and now I should do it in what way? I tried this:             AppModule().provideContext(TraktTvApp()), but I don't think this is the right way
– Sergei Mikhailovskii
                Jul 1, 2019 at 19:38
        
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