NoSuchMethodException 尝试实例化 ViewModel

Question

我正在尝试实例化我的视图模型，但出现此错误

原因：java.lang.NoSuchMethodException： [class com.test.domain.PostUserTokenImpl] at java.lang.Class.getConstructor0(Class.java：2327( at java.lang.Class.getConstructor(Class.java：1725( at com.test.presentation.viewmodel.LoginVMFactory.create(LoginVMFactory.kt：13(

我尝试做一个保存和接口的视图模型实例

视图

private val viewModel by lazy { ViewModelProviders.of(this, LoginVMFactory(PostUserTokenImpl(UserRepoImpl()))).get(LoginViewModel::class.java) }

LoginVMFactory

class LoginVMFactory(private val useCase: PostUserTokenImpl):ViewModelProvider.Factory {
override fun <T : ViewModel?> create(modelClass: Class<T>): T {
return modelClass.getConstructor(PostUserTokenImpl::class.java).newInstance(useCase)
}
}

登录视图模型

class LoginViewModel(private val useCase: PostUserToken): ViewModel() {
...
}

后用户令牌

interface PostUserToken {
suspend fun postUserToken(user: User): Resource<Boolean>
}

PostUserTokenImpl

class PostUserTokenImpl(private val repo: UserRepo): PostUserToken {
override suspend fun postUserToken(user:User):Resource<Boolean> = repo.saveUserToken(user)
}

知道为什么会这样吗？我怀疑这可能是因为我们无法使用接口实例化我们的视图模型？

Answer 1

将我的实现更改为

class LoginVMFactory(private val useCase: PostUserToken):ViewModelProvider.Factory {
override fun <T : ViewModel?> create(modelClass: Class<T>): T {
return modelClass.getConstructor(PostUserToken::class.java).newInstance(useCase)
}
}

然后在我看来

private val viewModel by lazy { ViewModelProviders.of(this, LoginVMFactory(PostUserTokenImpl(UserRepoImpl()))).get(LoginViewModel::class.java) }