为什么无法使用改造蚂蚁 MVVM 召回 API

Question

我使用MVVM架构模式在(登录(屏幕上工作，当使用错误的电子邮件或密码调用API并从API获得响应时遇到问题，然后编写正确的电子邮件和密码，API没有调用，旧的响应保持返回。

此外，我使用MVVM是否正确？

这是我的代码

public interface LoginApi {
@POST("/api/Login")
Call<LoginResponse> login(@Body LoginParams loginParams);
}

public class RetrofitService {
private static Retrofit retrofit;
private static final Object LOCK = new Object();
private static final String BASE_URL = "https://base.url";
public static Retrofit getRetrofitInstance() {
OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
httpClient.addInterceptor(new Interceptor() {
@Override
public Response intercept(Interceptor.Chain chain) throws IOException {
Request original = chain.request();
Request.Builder requestBuilder = original.newBuilder()
.addHeader("Content-Type", "application/json");
Request request = requestBuilder.build();
return chain.proceed(request);
}
});
OkHttpClient client = httpClient.build();
HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
logging.setLevel(HttpLoggingInterceptor.Level.BODY);
httpClient.addInterceptor(logging);
httpClient.readTimeout(60, TimeUnit.SECONDS);
httpClient.connectTimeout(60, TimeUnit.SECONDS);
if (retrofit == null) {
synchronized (LOCK) {
retrofit = new retrofit2.Retrofit.Builder()
.baseUrl(BASE_URL)
.client(client)
.addConverterFactory(GsonConverterFactory.create())
.client(httpClient.build())
.build();
}
}
return retrofit;
}
public static <S> S createService(Class<S> serviceClass) {
return getRetrofitInstance().create(serviceClass);
}
}

public class LoginRepository {
private static LoginRepository loginRepository;
static LoginRepository getInstance() {
if (loginRepository == null) {
loginRepository = new LoginRepository();
}
return loginRepository;
}
private LoginApi loginApi;
private LoginRepository() {
loginApi = RetrofitService.createService(LoginApi.class);
}
public MutableLiveData<LoginResponse> login(LoginParams loginParams) {
MutableLiveData<LoginResponse> loginData = new MutableLiveData<>();
loginApi.login(loginParams).enqueue(new Callback<LoginResponse>() {
@Override
public void onResponse(Call<LoginResponse> call,
Response<LoginResponse> response) {
loginData.setValue(response.body());
}
@Override
public void onFailure(Call<LoginResponse> call, Throwable t) {
}
});
return loginData;
}
}

public class LoginViewModel extends ViewModel {
private MutableLiveData<LoginResponse> mutableLiveData;
private LoginRepository loginRepository;
private LoginParams loginParams = new LoginParams();
public void init(Map<String, String> loginMap) {
if (mutableLiveData != null) {
return;
}
loginRepository = LoginRepository.getInstance();
loginParams.setEmail(loginMap.get("loginEmail"));
loginParams.setPassword(loginMap.get("loginPassword"));
mutableLiveData = loginRepository.login(loginParams);
}
public LiveData<LoginResponse> getLoginRepository() {
return mutableLiveData;
}
}

public class LoginFragment extends BaseFragment {
@BindView(R.id.et_email_login)
AppCompatEditText etEmailLogin;
@BindView(R.id.et_password_login)
AppCompatEditText etPasswordLogin;
public static LoginFragment getInstance() {
return new LoginFragment();
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View inflateFragmentView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_login, container, false);
ButterKnife.bind(this, view);
return view;
}
@OnClick(R.id.btn_enter_login)
public void onClickLogin() {
getMainActivity().showProgressBar();
LoginViewModel loginViewModel = ViewModelProviders.of(getActivity()).get(LoginViewModel.class);
loginViewModel.init(createLoginParam());
observeViewModel(loginViewModel);
loginViewModel.getLoginRepository();
}
private void observeViewModel(LoginViewModel loginViewModel) {
loginViewModel.getLoginRepository().observe(this, loginResponse -> {
getMainActivity().hideProgressBar();
if (loginResponse == null) {
// handle error here
return;
}
if (loginResponse.isSuccess()) {
getMainActivity().showResult(loginResponse.getUserId());

} else {
getMainActivity().showResult(loginResponse.getErrorMessage());
}
});
}

private Map<String, String> createLoginParam() {
Map<String, String> loginMap = new HashMap<>();
loginMap.put("loginEmail", etEmailLogin.getText().toString());
loginMap.put("loginPassword", etPasswordLogin.getText().toString());
return loginMap;
}
}

Answer 1

过了一段时间，我发现问题出现在LoginViewModel中，因为我没有创建mutableLiveData的新实例，所以我使用了预先创建的实例，每次都会给出相同的响应。所以我的问题通过消除这个条件解决了。

if (mutableLiveData != null) {
return;
}