Medium Post 2. ViewModelFactory

ViewModelFactory.kt

@Singleton
class ViewModelFactory @Inject constructor(private val creators: Map<Class<out ViewModel>, @JvmSuppressWildcards Provider<ViewModel>>?) : ViewModelProvider.Factory {

    @Suppress("UNCHECKED_CAST")
    override fun <T : ViewModel?> create(modelClass: Class<T>): T {

        var creator = creators!![modelClass]
        if (creator == null) {
            for (entry in creators.entries) {
                if (modelClass.isAssignableFrom(entry.key)) {
                    creator = entry.value
                    break
                }
            }
        }
        if (creator == null) {
            throw IllegalArgumentException("unknown model class " + modelClass)
        }
        try {
            return creator.get() as T
        } catch (e: Exception) {
            throw RuntimeException(e)
        }

    }

}