My ViewModel class is throwing a RunTimeException. It basically cannot create an instance of the ViewModel class. Here is the stacktrace:
2019-05-29 01:27:56.700 9698-9698/com.example.cryptpass_kt E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.cryptpass_kt, PID: 9698
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.cryptpass_kt/com.example.cryptpass_kt.MainActivity}: java.lang.RuntimeException: Cannot create an instance of class com.example.cryptpass_kt.EntryViewModel
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2853)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2928)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1609)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6703)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:769)
Caused by: java.lang.RuntimeException: Cannot create an instance of class com.example.cryptpass_kt.EntryViewModel
at androidx.lifecycle.ViewModelProvider$AndroidViewModelFactory.create(ViewModelProvider.java:208)
at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:135)
at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:103)
at com.example.cryptpass_kt.MainActivity.onCreate(MainActivity.kt:40)
at android.app.Activity.performCreate(Activity.java:6980)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2806)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2928)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1609)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6703)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:769)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at androidx.lifecycle.ViewModelProvider$AndroidViewModelFactory.create(ViewModelProvider.java:200)
at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:135)
at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:103)
at com.example.cryptpass_kt.MainActivity.onCreate(MainActivity.kt:40)
at android.app.Activity.performCreate(Activity.java:6980)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2806)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2928)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1609)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6703)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:769)
Caused by: java.lang.RuntimeException: cannot find implementation for com.example.cryptpass_kt.EntryDatabase. EntryDatabase_Impl does not exist
at androidx.room.Room.getGeneratedImplementation(Room.java:94)
at androidx.room.RoomDatabase$Builder.build(RoomDatabase.java:667)
at com.example.cryptpass_kt.EntryDatabase$Companion.getInstance(EntryDatabase.kt:17)
at com.example.cryptpass_kt.EntryRepository.<init>(EntryRepository.kt:12)
at com.example.cryptpass_kt.EntryViewModel.<init>(EntryViewModel.kt:8)
The error points to 4 different locations in the app, which are all rooted in the same problem. For example, these lines in the onCreate() method of my MainActivity.kt are in the stacktrace:
override fun onCreate(savedInstanceState: Bundle?) {
...
viewModel = ViewModelProviders.of(this).get(EntryViewModel::class.java)
viewModel.allEntries.observe(this, Observer { entries -> adapter.submitList(entries) })
...
}
I've followed some of the suggestions in SO, such as initializing the ViewModel object as lateinit and not null but so far it hasn't made any changes to the situation
EntryViewModel.kt
class EntryViewModel(application: Application) : AndroidViewModel(application) {
private val repository: EntryRepository = EntryRepository(application)
val allEntries: LiveData<List<Entry>>
init {
allEntries = repository.allEntries!!
}
fun insert(entry: Entry) {
repository.insert(entry)
}
fun update(entry: Entry) {
repository.update(entry)
}
fun delete(entry: Entry) {
repository.update(entry)
}
fun deleteAll() {
repository.deleteAllEntries()
}
}
EntryDatabase.kt
@Database(entities = [Entry::class], version = 1)
abstract class EntryDatabase : RoomDatabase() {
abstract fun entryDAO(): EntryDAO
companion object{
private var instance: EntryDatabase? = null
@Synchronized
fun getInstance(context: Context): EntryDatabase{
if(instance == null){instance = Room.databaseBuilder<EntryDatabase>(context.applicationContext, EntryDatabase::class.java, "entry_database").fallbackToDestructiveMigration().build()}
return instance as EntryDatabase
}
}
}
And I have all of the necessary gradle dependencies:
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
implementation 'androidx.appcompat:appcompat:1.0.2'
implementation 'androidx.core:core-ktx:1.0.2'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'androidx.recyclerview:recyclerview:1.1.0-alpha05'
implementation 'androidx.cardview:cardview:1.0.0'
implementation 'com.android.support:design:28.1.0'
implementation "android.arch.lifecycle:extensions:2.2.0-alpha01"
implementation "android.arch.persistence.room:runtime:2.1.0-beta01"
implementation "android.arch.paging:runtime:2.1.0-beta01"
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
implementation 'io.sentry:sentry-android:1.7.16'
implementation 'org.slf4j:slf4j-nop:1.7.25'
}
Try with this
val viewModel = ViewModelProviders.of(this).get(EntryViewModel::class.java)
and in your app build.gradle
implementation 'android.arch.lifecycle:extensions:1.1.1'