How ViewModelProviders works for https://medium.com/@josep.rodriguez/internals-of-android-architecture-components-part-i-the-viewmodel-d893e362a0d9

ViewModelProvidersOf.java

public static ViewModelProvider of(@NonNull Fragment fragment) {
    AndroidViewModelFactory factory = AndroidViewModelFactory.getInstance(checkApplication(checkActivity(fragment)));
    return new ViewModelProvider(ViewModelStores.of(fragment), factory);
}