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I am attempting to use the Android Dagger ‡ implementation and inject a DispatchingAndroidInjector into my Application class:

class MyApp : Application(), HasActivityInjector {
    private lateinit var dispatchingAndroidInjector: DispatchingAndroidInjector<Activity>
        @Inject set    
    override fun onCreate() {
        super.onCreate()
        AppInjector.init(this)
    override fun activityInjector(): ActivityInjector<Activity> {
        return dispatchingAndroidInjector
But I get an IllegalArgumentExecption stating that the "lateinit property has not been initialized":
06-19 10:57:30.773 10797-10797/com.example.app E/AndroidRuntime: FATAL EXCEPTION: main
        Process: com.example.app, PID: 10797
        java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.app/com.example.app.ui.MainActivity}: kotlin.UninitializedPropertyAccessException: lateinit property dispatchingAndroidInjector has not been initialized
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2666)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2727)
            at android.app.ActivityThread.-wrap12(ActivityThread.java)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1478)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:154)
            at android.app.ActivityThread.main(ActivityThread.java:6121)
            at java.lang.reflect.Method.invoke(Native Method)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)
         Caused by: kotlin.UninitializedPropertyAccessException: lateinit property dispatchingAndroidInjector has not been initialized
            at com.example.app.MyApp.activityInjector(MyApp.kt:28)
            at dagger.android.AndroidInjection.inject(AndroidInjection.java:55)
            at com.example.app.injection.AppInjector.handleActivity(AppInjector.kt:41)
            at com.example.app.injection.AppInjector.access$handleActivity(AppInjector.kt:14)
            at com.example.app.injection.AppInjector$init$1.onActivityCreated(AppInjector.kt:21)
            at android.app.Application.dispatchActivityCreated(Application.java:197)
            at android.app.Activity.onCreate(Activity.java:961)
            at android.support.v4.app.BaseFragmentActivityGingerbread.onCreate(BaseFragmentActivityGingerbread.java:54)
            at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:319)
            at com.example.app.ui.MainActivity.onCreate(MainActivity.kt:20)
            at android.app.Activity.performCreate(Activity.java:6682)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2619)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2727) 
            at android.app.ActivityThread.-wrap12(ActivityThread.java) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1478) 
            at android.os.Handler.dispatchMessage(Handler.java:102) 
            at android.os.Looper.loop(Looper.java:154) 
            at android.app.ActivityThread.main(ActivityThread.java:6121) 
            at java.lang.reflect.Method.invoke(Native Method) 
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889) 
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)
This is the AppInjector class used to create the AppComponent and inject the MyApp dependencies:
object AppInjector {
    fun init(app: MyApp) {
        DaggerAppComponent.builder().application(app).build().inject(app)
        // ...
And the AppComponent interface:
@Singleton
@Component(modules = arrayOf(
    AndroidInjectionModule::class,
    AppModule::class,
    MainActivityModule::class
)) interface AppComponent {
    @Component.Builder interface Builder {
        @BindsInstance fun application(app: Application): Builder
        fun build(): AppComponent
    fun inject(app: MyApp)
I am using the @Inject annotation on the property accessor, as outlined in the documentation, but it doesn't seem to be working. What am I doing wrong?
I can't test it right now, but I think it's because your property is private. Dagger doesn't use reflection, so the fields it injects have to be visible from outside the class in order for it to operate. 
(Writing out set explicitly doesn't help with this, as it just represents a private setter in this case. Note that fields are private for all properties, and non-private properties have getters/setters with broader visibilities as appropriate.)
You should also be able to just annotate the property instead of its setter, so this would be the end result:
@Inject
lateinit var dispatchingAndroidInjector: DispatchingAndroidInjector<Activity>
If you want your property to be private, consider using constructor injection instead.
change this
private lateinit var dispatchingAndroidInjector: DispatchingAndroidInjector<Activity>
    @Inject set 
private internal var dispatchingAndroidInjector: DispatchingAndroidInjector<Activity>
    @Inject set 
        
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