如果没有@Inject构造函数或@Providers带注释的方法，就无法提供java.lang.String

Question

抛出的错误或两者兼有：

@Inject
@Named("DummyString")
lateinit var dummyString: String
@Inject
@Named("SomethingToRemember")
lateinit var sthToRemember: String

但以下是可以的：

@Inject
@Named("MySharedPrefs")
lateinit var mySharedPreferences: SharedPreferences

dagger串的提供和使用有什么特别之处吗？

我的模块

@Provides
@JvmStatic
@Singleton
@Named("MySharedPrefs")
fun provideMySharedPrefs(context: Context) : SharedPreferences {
return context.getSharedPreferences("MySharedPrefs", Context.MODE_PRIVATE)
}
@Provides
@JvmStatic
@Singleton
@Named("DummyString")
fun provideDummyString(): String {
return "dummy dummy"
}
@Provides
@JvmStatic
@Singleton
@Named("SomethingToRemember")
fun provideSthToRemember(@Named("MySharedPrefs") sharedPreferences: SharedPreferences) : String {
return sharedPreferences.getString("SomethingToRemember", "") ?: ""
}

错误详细信息：

error: [Dagger/MissingBinding] java.lang.String cannot be provided without an @Inject constructor or an @Provides-annotated method.
public abstract interface FormsPreviewAppComponent extends dagger.android.AndroidInjector<com.myapp.android.MyApplication> {
^
java.lang.String is injected at
com.myapp.android.MyLinkActivity.sthToRemember
com.myapp.android.MyActivity is injected at
dagger.android.AndroidInjector.inject(T) [com.myapp.android.MyAppComponent → com.myapp.android.MyAppModule_Bindable_ContributesMyActivity.MyActivitySubcomponent]
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':myapp:kaptDebugKotlin'.
> A failure occurred while executing org.jetbrains.kotlin.gradle.internal.KaptExecution
> java.lang.reflect.InvocationTargetException (no error message)

Answer 1

我需要使用@field:Named("DummyString")而不是@Named("DummyString")https://github.com/google/dagger/issues/848