IllegalArgumentException: savedInstanceState Specified as Non-Null is Null

Question

I am getting a strange error when I start my MainActivity:

06-16 16:01:05.193 2083-2083/? E/AndroidRuntime: FATAL EXCEPTION: main         Process: com.android.example.github, PID: 2083         java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.example.github/com.android.example.github.ui.MainActivity}: java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter savedInstanceState             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: java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter savedInstanceState             at com.android.example.github.injection.AppInjector$init$1.onActivityCreated(AppInjector.kt)             at android.app.Application.dispatchActivityCreated(Application.java:197)             at android.app.Activity.onCreate(Activity.java:961)             at android.support.v4.app.BaseFragmentActivityGingerbread.onCreate(BaseFragmentActivityGingerbread.java:54)             at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:319)             at com.android.example.github.ui.MainActivity.onCreate(MainActivity.kt:20)             at android.app.Activity.performCreate(Activity.java:6682)             at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2619)             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2727)              at android.app.ActivityThread.-wrap12(ActivityThread.java)              at android.app.ActivityThread$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 my MainActivity class:

class MainActivity : LifecycleActivity(), HasSupportFragmentInjector {      lateinit var dispatchingAndroidInjector: DispatchingAndroidInjector<Fragment>         @Inject set      lateinit var navigationController: NavigationController      override fun onCreate(savedInstanceState: Bundle?) {         super.onCreate(savedInstanceState)         setContentView(R.layout.main_activity)          if (savedInstanceState == null) {             navigationController.navigateToSearch()         }     }      override fun supportFragmentInjector(): AndroidInjector<Fragment> {         return dispatchingAndroidInjector     }  } 

The error states that the parameter savedInstanceState is null, when it is specified as non-null; but it is nullable (savedInstanceState: Bundle?) and the onCreate() method is marked as @Nullable in the source.

I have not come across this error in any of my other Kotlin projects. I am using Kotlin version 1.1.2-5; and had the same error with 1.1.2-3.

Answer 1

I had the exact same problem, you have to make nullable types here:

override fun onCreatePreferences(bundle: Bundle?, s: String?) {} 

Answer 2

The issue is in the AppInjector. I used the google GitHubBrowser sample like you did and ran into this same error. I copied the code over to my project and let Android Studio convert it to Kotlin. When it did this it didn't properly specify the nullability of the savedInstanceState parameter which is what is causing the crash. Just make it optional like in the below code and it will work.

object AppInjector {     fun init(app: App) {         DaggerAppComponent.builder().application(app)                 .build().inject(app)         app                 .registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {                     override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) {                         handleActivity(activity)                     }                      override fun onActivityStarted(activity: Activity) {                      }                      override fun onActivityResumed(activity: Activity) {                      }                      override fun onActivityPaused(activity: Activity) {                      }                      override fun onActivityStopped(activity: Activity) {                      }                      override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) {                      }                      override fun onActivityDestroyed(activity: Activity) {                      }                 })     }      private fun handleActivity(activity: Activity) {         if (activity is HasSupportFragmentInjector) {             AndroidInjection.inject(activity)         }         (activity as? FragmentActivity)?.supportFragmentManager?.registerFragmentLifecycleCallbacks(                 object : FragmentManager.FragmentLifecycleCallbacks() {                     override fun onFragmentCreated(fm: FragmentManager?, f: Fragment?,                                                    savedInstanceState: Bundle?) {                         if (f is Injectable) {                             AndroidSupportInjection.inject(f)                         }                     }                 }, true)     } }