mlykotom

@Component(
	dependencies = [
		FeatureComponent::class
	]
)
@Singleton
interface AppComponent {

	@Component.Factory
	interface Factory {

mlykotom

class SomeViewModel @Inject constructor(
  private val depFromDagger1: Dependency,
  private val depFromDagger2: Dependency2
) : ViewModel()

mlykotom

class SomeViewModel(
  private val dep1: Dependency,
  private val dep2: Dependency2
) : ViewModel()

mlykotom

class SomeViewModel @AssistedInject constructor(
    private val application: Application,
    @Assisted private val savedStateHandle: SavedStateHandle
){
    // must be inside of the ViewModel class!
    @AssistedFactory
    interface Factory : AssistedSavedStateViewModelFactory<SomeViewModel> {
        override fun create(savedStateHandle: SavedStateHandle): SomeViewModel  // may be ommited prior kotlin 1.3.60 or after PR #121 in AssistedInject lib
    }
}

mlykotom

class SomeViewModel @AssistedInject constructor(
   private val application: Application,
   @Assisted private val savedStateHandle: SavedStateHandle
){
  // ...
}

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/**
 * Base interface for all ViewModel factories
 */
interface AssistedSavedStateViewModelFactory<T : ViewModel> {
   fun create(savedStateHandle: SavedStateHandle): T
}

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class SomeViewModel(/* ..ommited.. */){
  val counter = savedStateHandle.getLiveData("counter", 0)

  fun onPlusClick() {
    counter.value = (counter.value ?: 0) + 1
  }
}

mlykotom

class SomeViewModel(/* ..ommited.. */){
  val counter = MutableLiveData<Int>(0)

  init {
    counter.value = savedStateHandle.get("counter") ?: 0
    
    counter.observeForever { newValue ->
      savedStateHandle.set("counter", newValue)
    }
  }

mlykotom

class SomeViewModel(
   private val application: Application,
   private val savedStateHandle: SavedStateHandle
){
  // ...
}

mlykotom

class SomeFragment : Fragment() {
  
  lateinit var viewModel : SomeViewModel
  
  override fun onCreate(savedState: Bundle?){
    super.onCreate(savedState)    
    // default arguments, so you can set something dynamically
    val defaultArgs: Bundle? = bundleOf("id" to 5) // may be null
    
    // default factory for ViewModel creation