DataBInding livedata Room

//database helper
@Database(entities = {Contact.class}, version = 1, exportSchema = false)
@TypeConverters(AddressTypeConverter.class)
public abstract class TaskDatabase extends RoomDatabase {

    public abstract ContactDao taskDao();

    public static TaskDatabase sInstance;

    // Get a database instance    public static synchronized TaskDatabase getDatabaseInstance(Context context) {
        if (sInstance == null) {
            sInstance = create(context);
        }
        return sInstance;
    }

    // Create the database    static TaskDatabase create(Context context) {
        Builder<TaskDatabase> builder = Room.databaseBuilder(context.getApplicationContext(),
                TaskDatabase.class,
                "Contact");
        return builder.build();
    }
}

public class ContactDatabaseViewModel extends AndroidViewModel {


    private ContactDao mTaskDao;

    public ContactDatabaseViewModel(@NonNull Application application) {
        super(application);
        mTaskDao = TaskDatabase.getDatabaseInstance(application).taskDao();
    }

    public int createFirstRecord() {
        Contact model = new Contact();
        model.setId(1);
        return (int) mTaskDao.createFirstRecord(model);
    }
/*    public int reset() {        mTaskDao.reset();        return (int) createFirstRecord();    }*/
    public LiveData<String> getNameFromDatabase() {
        return mTaskDao.getNameFromDatabase();
    }
    public Contact getContact() {
        return mTaskDao.getContact();
    }

    public LiveData<String> getEmailId() {
        return mTaskDao.getEmailId();
    }

    public LiveData<String> getMobileNo() {
        return mTaskDao.getMobileNo();
    }

    public LiveData<Boolean> getIsAlternateAddress() {
        return mTaskDao.isAlternateAddress();
    }



    public LiveData<Address> getAddress() {
        return mTaskDao.getAddress();
    }
    public Address getAddress1() {
        return mTaskDao.getAddress1();
    }

    public int updateAlterNateAddress(Boolean state) {
        return (int) mTaskDao.updateAlterNateAddress(state);
    }
    public long updateName(Contact model) {
        return (int) mTaskDao.updateName(model.getName());
    }

    public long updateEmailId(String value) {
        return (int) mTaskDao.updateEmailId(value);
    }

    public long updateMobileNo(String value) {
        return (int) mTaskDao.updatemobileNo(value);
    }



    public long updateAddress(String key, String value) {
        Address address = mTaskDao.getAddress1();
        if (address == null) {
            address = new Address();
        }
        switch (key) {
            case "state":
                address.setState(value);
                break;
            case "district":
                address.setDistrict(value);
                break;
            case "location":
                address.setLocation(value);
                break;
            case "pincode":
                if (value.equals(""))
                    value = "0";
                address.setPincode(Integer.parseInt(value));
                break;
        }
        return (int) mTaskDao.updateAddress(address);
    }




}

//to qury fire
ew AsyncTask<String, Integer, String>() {
    @Override    protected String doInBackground(String... args) {
        Contact model = new Contact();
        model.setName(args[0]);
        contactDatabaseViewModel = ViewModelProviders.of(context).get(ContactDatabaseViewModel.class);
contactDatabaseViewModel.updateName(model);
        return "";
    }
}.execute(textView.getText().toString().trim());


//to set live data on observer
contactDatabaseViewModel.getNameFromDatabase().observe(mContext, new Observer<String>() {
    @Override    public void onChanged(@Nullable String s) {
        if (s != null)
            if (!s.equals("")) {
                nameCardVisiblity = false;
                notifyVisiblity(BR.nameCardVisiblity);
            }
    }
});