More efficient way getting LiveData object

I have a LiveData<List<Storage>> in my StorageViewModel, I want to get this list in an activity in order to perform a get(id) on it.

Though so far I can only achieve one way to get the this List<Storage> without it being null, except that way does not feel efficient to me.

Why does my second method not work? Am I forgetting declaring something final?

EDIT: my second method retrieves an object coming from an async call on a ROOM repository, I require some sort of callback to get the right instance as it seems. Then again, perhaps the way could be more efficient.

ViewModel Class

public class StorageViewModel extends AndroidViewModel
{
    StorageRepository _repository;

    LiveData<List<Storage>> _storages;

    public ObservableField<String> storageName = new ObservableField<>("");
    public ObservableField<String> storageLoc = new ObservableField<>("");

    public StorageViewModel(Application application)
    {
        super(application);
        _repository = new StorageRepository(application);
        _storages = _repository.getAllStorages();
    }

    public LiveData<List<Storage>> getStorages()
    {
        return _storages;
    }

    public void addStorage(String storageName, String storageLocation)
    {
        _repository.insert(new Storage(storageName, storageLocation));
    } 
}

Working method in StorageActivity Class (storages != null)

void setActivityElements()
{
    int id = (int) getIntent().getExtras().get("storageID");

    storageVM.getStorages().observe(this, new Observer<List<Storage>>() 
    {
        @Override
        public void onChanged(@Nullable final List<Storage> storages) 
        {
            Storage storage = storages.get(id); // storages != null
        }
    });
}

Not working method in StorageActivity Class (storages == null)

void setActivityElements()
{
    int id = (int) getIntent().getExtras().get("storageID");

    List<Storage> storages = storageVM.getStorages().getValue(); // storages == null

    Storage storage = storages.get(id);
}