我正在尝试实例化我的 View 模型,但出现此错误
Caused by: 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)
我尝试做一个持有和接口(interface)的 ViewModel 实例
看法
private val viewModel by lazy { ViewModelProviders.of(this, LoginVMFactory(PostUserTokenImpl(UserRepoImpl()))).get(LoginViewModel::class.java) }
登录VMFactory
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 View 模型
class LoginViewModel(private val useCase: PostUserToken): ViewModel() {
...
}
PostUserToken
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不能用我们的 View 模型的接口(interface)实例化?
最佳答案
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) }
关于android - NoSuchMethodException 试图实例化 ViewModel,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/59379305/