joseprl89

public HolderFragment() {
    setRetainInstance(true);
}

joseprl89

HolderFragment holderFragmentFor(Fragment parentFragment) {
    FragmentManager fm = parentFragment.getChildFragmentManager();
    HolderFragment holder = findHolderFragment(fm);
    if (holder != null) {
        return holder;
    }
    holder = mNotCommittedFragmentHolders.get(parentFragment);
    if (holder != null) {
        return holder;
    }

joseprl89

public static ViewModelStore of(@NonNull Fragment fragment) {
    if (fragment instanceof ViewModelStoreOwner) {
        return ((ViewModelStoreOwner) fragment).getViewModelStore();
    }
    return holderFragmentFor(fragment).getViewModelStore();
}

...

public static HolderFragment holderFragmentFor(Fragment fragment) {

joseprl89

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

joseprl89

public <T extends ViewModel> T get(@NonNull Class<T> modelClass) {
    String canonicalName = modelClass.getCanonicalName();
    if (canonicalName == null) {
        throw new IllegalArgumentException("Local and anonymous classes can not be ViewModels");
    }
    return get(DEFAULT_KEY + ":" + canonicalName, modelClass);
}

public <T extends ViewModel> T get(@NonNull String key, @NonNull Class<T> modelClass) {
    ViewModel viewModel = mViewModelStore.get(key);

joseprl89

public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
    try {
        return modelClass.newInstance();
    } catch (InstantiationException e) {
        ...
    }
}

joseprl89

@NonNull
@Override
public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
    if (AndroidViewModel.class.isAssignableFrom(modelClass)) {
        try {
            return modelClass.getConstructor(Application.class).newInstance(mApplication);
        } catch ... {
            ...
        }
    }

joseprl89

final void put(String key, ViewModel viewModel) {
    ViewModel oldViewModel = mMap.get(key);
    if (oldViewModel != null) {
        oldViewModel.onCleared();
    }
    mMap.put(key, viewModel);
}

final ViewModel get(String key) {
    return mMap.get(key);

joseprl89

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

joseprl89

public void onCreate(Bundle savedInstanceState) {
    MyViewModel model = ViewModelProviders.of(this).get(MyViewModel.class);
    model.getUsers().observe(this, users -> {
        // update UI
    });
}