如何在Android中使用Dagger2将字符串传递给ViewModel/Repository类？

这是我的片段类：

public class MyFragment extends DaggerFragment {
    @Inject MyViewModelFactory factory;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle bundle) {
        String uid = "123"; //How to pass this String??
        MyViewModel viewModel = ViewModelProviders.of(this, factory).get(MyViewModel.class);
        LiveData<User> liveData = viewModel.getUserLiveData();
    }
}

这个

MyRepository

类：

public class MyViewModel extends ViewModel {
    private MutableLiveData<User> liveData;

    @Inject
    MyViewModel(MyRepository repository) {
        userLiveData = repository.addUserToLiveData();
        //Here I need the value of that String "123"
    }

    LiveData<User> getUserLiveData() {
        return liveData;
    }
}

@Singleton
class MyRepository {
    private Retrofit retrofit;

    @Inject
    MyRepository(Retrofit retrofit) {
        //Or here I need the value of that String "123"
    }

    MutableLiveData<User> addUserToLiveData() {
        //Make api call using retrofit
    }
}

@Module
public class AppModule {
    @Singleton
    @Provides
    static Retrofit provideRetrofit(){
        return new Retrofit.Builder()... //Initialize retrofit
    }
}

@Module
abstract class MyViewModelModule {
    @Binds
    abstract ViewModelProvider.Factory bindMyViewModelFactory(MyViewModelFactory factory);

    @Binds
    @IntoMap
    @ViewModelKey(MyViewModel.class)
    abstract ViewModel provideMyViewModel(MyViewModel viewModel);
}

在

MyViewModelModule

class中：

public class MyViewModel extends ViewModel {
    private MutableLiveData<User> liveData;

    @Inject
    MyViewModel(MyRepository repository) {
        userLiveData = repository.addUserToLiveData();
        //Here I need the value of that String "123"
    }

    LiveData<User> getUserLiveData() {
        return liveData;
    }
}

@Singleton
class MyRepository {
    private Retrofit retrofit;

    @Inject
    MyRepository(Retrofit retrofit) {
        //Or here I need the value of that String "123"
    }

    MutableLiveData<User> addUserToLiveData() {
        //Make api call using retrofit
    }
}

@Module
public class AppModule {
    @Singleton
    @Provides
    static Retrofit provideRetrofit(){
        return new Retrofit.Builder()... //Initialize retrofit
    }
}

@Module
abstract class MyViewModelModule {
    @Binds
    abstract ViewModelProvider.Factory bindMyViewModelFactory(MyViewModelFactory factory);

    @Binds
    @IntoMap
    @ViewModelKey(MyViewModel.class)
    abstract ViewModel provideMyViewModel(MyViewModel viewModel);
}

---

我尝试的是在ViewModel/repository构造函数中添加字符串，但没有成功。请帮助我将该

uid

传递给ViewModel或repository类。谢谢

一种可能的解决方案是每个viewmodel有一个工厂，然后将UID设置为工厂，工厂将其传递给viewmodel

class MyViewModelFactory @Inject constructor(
        private val repository: Repository
): ViewModelProvider.Factory {

    lateinit var uid: String

    @Suppress("UNCHECKED_CAST")
    override fun <T : ViewModel> create(modelClass: Class<T>): T =
            if (modelClass.isAssignableFrom(MyViewModel::class.java)) {
                    MyViewModel(
                        repository,
                        uid
                ) as T
            } else {
                throw IllegalArgumentException("Unknown ViewModel class [$modelClass]")
            }
}

类MyViewModelFactory@Inject构造函数(
专用val存储库：存储库
)：ViewModelProvider.Factory{
lateinit变量uid:字符串
@抑制（“未选中的_CAST”）
重写趣味创建（modelClass:Class）：T=
if（modelClass.isAssignableFrom（MyViewModel:：class.java））{
MyViewModel(
存储库，
液体
)as T
}否则{
抛出IllegalArgumentException（“未知的ViewModel类[$modelClass]”）
}
}

然后

@Nullable
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、捆绑包）{
String uid=“123”//如何传递此字符串？？
setUid（uid）；
MyViewModel viewModel=ViewModelProviders.of（this，factory）.get（MyViewModel.class）；
LiveData LiveData=viewModel.getUserLiveData（）；
}

编辑：在Java中

public final class MyViewModelFactory implements Factory {
    private final Repository repository;
    private String uid;

   @Inject
   public MyViewModelFactory(Repository repository) {
      this.repository = repository;
   }

   @NotNull
   public ViewModel create(@NotNull Class modelClass) {
      if (modelClass.isAssignableFrom(MyViewModel.class)) {
         return new MyViewModel(repository, uid);
      } else {
         throw (Throwable)(new IllegalArgumentException("Unknown ViewModel class [" + modelClass + ']'));
      }
   }

   public void setUid(@NonNull final String uid) {
       this.uid = uid;
   }
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle bundle) {
    String uid = "123"; //How to pass this String??
    factory.setUid(uid);
    MyViewModel viewModel = ViewModelProviders.of(this, factory).get(MyViewModel.class);
    LiveData<User> liveData = viewModel.getUserLiveData();
}

公共最终类MyViewModelFactory实现工厂{
私有最终存储库；
私有字符串uid；
@注入
公共MyViewModelFactory（存储库）{
this.repository=存储库；
}
@NotNull
公共视图模型创建（@NotNull类modelClass）{
if（modelClass.isAssignableFrom（MyViewModel.class））{
返回新的MyViewModel（存储库，uid）；
}否则{
throw（Throwable）（新的IllegalArgumentException（“未知的ViewModel类[“+modelClass+”]）；
}
}
public void setUid（@NonNull final String uid）{
this.uid=uid；
}
}
@可空
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、捆绑包）{
String uid=“123”//如何传递此字符串？？
setUid（uid）；
MyViewModel viewModel=ViewModelProviders.of（this，factory）.get（MyViewModel.class）；
LiveData LiveData=viewModel.getUserLiveData（）；
}

一种可能的解决方案是每个viewmodel有一个工厂，然后将UID设置为工厂，工厂将其传递给viewmodel

class MyViewModelFactory @Inject constructor(
        private val repository: Repository
): ViewModelProvider.Factory {

    lateinit var uid: String

    @Suppress("UNCHECKED_CAST")
    override fun <T : ViewModel> create(modelClass: Class<T>): T =
            if (modelClass.isAssignableFrom(MyViewModel::class.java)) {
                    MyViewModel(
                        repository,
                        uid
                ) as T
            } else {
                throw IllegalArgumentException("Unknown ViewModel class [$modelClass]")
            }
}

类MyViewModelFactory@Inject构造函数(
专用val存储库：存储库
)：ViewModelProvider.Factory{
lateinit变量uid:字符串
@抑制（“未选中的_CAST”）
重写趣味创建（modelClass:Class）：T=
if（modelClass.isAssignableFrom（MyViewModel:：class.java））{
MyViewModel(
存储库，
液体
)as T
}否则{
抛出IllegalArgumentException（“未知的ViewModel类[$modelClass]”）
}
}

然后

@Nullable
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、捆绑包）{
String uid=“123”//如何传递此字符串？？
setUid（uid）；
MyViewModel viewModel=ViewModelProviders.of（this，factory）.get（MyViewModel.class）；
LiveData LiveData=viewModel.getUserLiveData（）；
}

编辑：在Java中

public final class MyViewModelFactory implements Factory {
    private final Repository repository;
    private String uid;

   @Inject
   public MyViewModelFactory(Repository repository) {
      this.repository = repository;
   }

   @NotNull
   public ViewModel create(@NotNull Class modelClass) {
      if (modelClass.isAssignableFrom(MyViewModel.class)) {
         return new MyViewModel(repository, uid);
      } else {
         throw (Throwable)(new IllegalArgumentException("Unknown ViewModel class [" + modelClass + ']'));
      }
   }

   public void setUid(@NonNull final String uid) {
       this.uid = uid;
   }
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle bundle) {
    String uid = "123"; //How to pass this String??
    factory.setUid(uid);
    MyViewModel viewModel = ViewModelProviders.of(this, factory).get(MyViewModel.class);
    LiveData<User> liveData = viewModel.getUserLiveData();
}

公共最终类MyViewModelFactory实现工厂{
私有最终存储库；
私有字符串uid；
@注入
公共MyViewModelFactory（存储库）{
this.repository=存储库；
}
@NotNull
公共视图模型创建（@NotNull类modelClass）{
if（modelClass.isAssignableFrom（MyViewModel.class））{
返回新的MyViewModel（存储库，uid）；
}否则{
throw（Throwable）（新的IllegalArgumentException（“未知的ViewModel类[“+modelClass+”]）；
}
}
public void setUid（@NonNull final String uid）{
this.uid=uid；
}
}
@可空
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、捆绑包）{
String uid=“123”//如何传递此字符串？？
setUid（uid）；
MyViewModel viewModel=ViewModelProviders.of（this，factory）.get（MyViewModel.class）；
LiveData LiveData=viewModel.getUserLiveData（）；
}

好的，让我检查一下，然后再打给你。这让我很难理解，因为它在科特林，我对它不太熟悉：|做不好。哦，非常感谢你。现在好多了。我现在就试试看，然后再给你打电话。好吧，让我检查一下，然后再给你打电话。这让我很难理解，因为它在科特林，而且我对它不太熟悉：|做不好。哦，非常感谢你。现在好多了。我现在就去试试，然后再打给你。