Android：注入了 hilt throws 的 ViewModel 没有零参数构造函数”

Question

我将我的应用程序从 dagger2 手动迁移到 hilt。我没有遇到任何编译或构建错误。但是当我尝试运行我的应用程序时，它在初始屏幕上崩溃了这个堆栈：

E/AndroidRuntime: FATAL EXCEPTION: main
Process: pfe.usdb.dictili, PID: 7815
java.lang.RuntimeException: Unable to start activity ComponentInfo{pfe.usdb.dictili/pfe.usdb.dictili.view.auth.SplashScreen}: java.lang.RuntimeException: Cannot create an instance of class pfe.usdb.dictili.viewmodel.auth.AuthVModel
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3449)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:223)
    at android.app.ActivityThread.main(ActivityThread.java:7656)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
 Caused by: java.lang.RuntimeException: Cannot create an instance of class pfe.usdb.dictili.viewmodel.auth.AuthVModel
    at androidx.lifecycle.ViewModelProvider$NewInstanceFactory.create(ViewModelProvider.java:221)
    at androidx.lifecycle.ViewModelProvider$AndroidViewModelFactory.create(ViewModelProvider.java:278)
    at androidx.lifecycle.SavedStateViewModelFactory.create(SavedStateViewModelFactory.java:106)
    at androidx.hilt.lifecycle.HiltViewModelFactory.create(HiltViewModelFactory.java:74)
    at androidx.lifecycle.AbstractSavedStateViewModelFactory.create(AbstractSavedStateViewModelFactory.java:69)
    at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:185)
    at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150)
    at androidx.lifecycle.ViewModelLazy.getValue(ViewModelProvider.kt:54)
    at androidx.lifecycle.ViewModelLazy.getValue(ViewModelProvider.kt:41)
    at pfe.usdb.dictili.view.auth.SplashScreen.getViewModel(Unknown Source:2)
    at pfe.usdb.dictili.view.auth.SplashScreen.onCreate(SplashScreen.kt:46)
    at android.app.Activity.performCreate(Activity.java:8000)
    at android.app.Activity.performCreate(Activity.java:7984)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3422)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:223) 
    at android.app.ActivityThread.main(ActivityThread.java:7656) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) 
 Caused by: java.lang.InstantiationException: java.lang.Class<pfe.usdb.dictili.viewmodel.auth.AuthVModel> has no zero argument constructor
    at java.lang.Class.newInstance(Native Method)
    at androidx.lifecycle.ViewModelProvider$NewInstanceFactory.create(ViewModelProvider.java:219)
    at androidx.lifecycle.ViewModelProvider$AndroidViewModelFactory.create(ViewModelProvider.java:278) 
    at androidx.lifecycle.SavedStateViewModelFactory.create(SavedStateViewModelFactory.java:106) 
    at androidx.hilt.lifecycle.HiltViewModelFactory.create(HiltViewModelFactory.java:74) 
    at androidx.lifecycle.AbstractSavedStateViewModelFactory.create(AbstractSavedStateViewModelFactory.java:69) 
    at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:185) 
    at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150) 
    at androidx.lifecycle.ViewModelLazy.getValue(ViewModelProvider.kt:54) 
    at androidx.lifecycle.ViewModelLazy.getValue(ViewModelProvider.kt:41) 
    at pfe.usdb.dictili.view.auth.SplashScreen.getViewModel(Unknown Source:2) 
    at pfe.usdb.dictili.view.auth.SplashScreen.onCreate(SplashScreen.kt:46) 
    at android.app.Activity.performCreate(Activity.java:8000) 
    at android.app.Activity.performCreate(Activity.java:7984) 
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309) 
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3422) 
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:223) 
    at android.app.ActivityThread.main(ActivityThread.java:7656) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)

它说它无法创建该视图模型的实例，因为它没有零参数构造函数，但是： 1- 我的视图模型 class 注入了刀柄（BaseViewModel 是抽象的）：

class AuthVModel @ViewModelInject constructor(
private val sharedPreferences: PreferencesRepository,
private val authRepository: AuthRepository
) : BaseViewModel()

2-我的activity注解了AndroidEntryPoint（BaseActivity是抽象的）：

@AndroidEntryPoint
class SplashScreen : BaseActivity() {

private val viewModel: AuthVModel by viewModels()

3- 视图模型所依赖的存储库已正确注入，android studio 4.1.1 在左侧显示注入图标：

class AuthRepository @Inject constructor(
@NonAuthenticatedAuthenticationService private val unauthorizedService: AuthService,
@AuthenticatedAuthenticationService private val authorizedService: AuthService
) 

class PreferencesRepository @Inject constructor(
private val sharedPreferences: SharedPreferences
)

我不知道这里发生了什么，这不是我第一次使用它，因为我最近构建了一些应用程序就是这样（一些代码是 100% 从这些项目中复制的）。

Answer 1

您是否在模块的 gradle.build 文件中将 required dependency 用于 Jetpack 组件（在您的情况下为 ViewModel）？
即：

kapt "androidx.hilt:hilt-compiler:$hiltJetpackVer"
implementation "androidx.hilt:hilt-lifecycle-viewmodel:$hiltJetpackVer"

请注意，该版本与用于主要刀柄依赖项的版本不同。

Android：注入了 hilt throws 的 ViewModel 没有零参数构造函数”

Android: ViewModel injected with hilt throws has no zero argument constructor"

android

android-viewmodel

dagger-hilt