Firestore子集合返回空无报错，Android+Hilt环境求排查指导

问题背景 #

我正在开发一款Android应用，目标是获取特定用户Firestore中plants子集合的所有植物数据。Firestore数据结构为：users集合 -> 单个用户文档 -> plants子集合，每个植物文档包含id、plant_category_id、image、name等字段。

现有代码 #

仓库实现类（PlantRepositoryImpl） #

@Singleton
class PlantRepositoryImpl @Inject constructor(
    private val userRef: CollectionReference
): PlantRepository {
    override fun getPlantsFromFirestore() = callbackFlow {

   
       val user = Firebase.auth.currentUser!!.uid
       // Log.d("Data:","${user}")
        val snapshotListener = userRef.document(user).collection("plants").orderBy("name").addSnapshotListener{ snapshot, e ->

            val response = if (snapshot != null) {
                val plant = snapshot.toObjects(Plant::class.java)

                Success(plant)
            } else {
                Error(e?.message ?: e.toString())
            }
            trySend(response).isSuccess
        }
        awaitClose {
            snapshotListener.remove()
        }
    }
}

Hilt依赖注入模块（AppModule） #

@Module
@InstallIn(SingletonComponent::class)
object AppModule {
    @Provides
    fun provideFirebaseFirestore()= Firebase.firestore

    @Provides
    fun provideUserRef(
       db: FirebaseFirestore

   )=db.collection("users")

   @Provides
    fun provideUserRepository(
       userRef: CollectionReference
 ): PlantRepository = PlantRepositoryImpl(userRef)

    @Provides
    fun provideUseCases(
        repo: PlantRepository
    ) = UseCases(
        getPlants = GetPlants(repo),
        addPlant = AddPlant(repo),
        deletePlant = DeletePlant(repo),
        editPlant= EditPlant(repo)

    )
}

Plant数据类 #

data class Plant(
    val id:String?=null,
    val plant_category_id:String?=null,
    val image:String?=null,
    val name:String?=null,
    val category:String?=null,
    val room_location:String?=null,
)

MainActivity #

@AndroidEntryPoint
class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            IndoorPlantCareTheme {
                val navController = rememberNavController()
                SetupNavGraph(navController = navController)
            }
        }
    }
}

自定义Application类（IndoorPlantCare） #

@HiltAndroidApp
class IndoorPlantCare: Application()

Manifest配置 #

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.indoorplantcare">
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:name=".IndoorPlantCare"
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.IndoorPlantCare"
        tools:targetApi="31"
        tools:ignore="MissingClass">
        <activity
            android:name=".MainActivity"
            android:exported="true"
            android:label="@string/app_name"
            android:theme="@style/Theme.IndoorPlantCare">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

UI代码 #

when (plantResponse) {
    is Loading -> ProgressBar()
    is Success ->LazyColumn(
        modifier = Modifier
            .fillMaxSize()
            .background(Color.White)
    ) {
      
        items(items = plantResponse.data) {
            CardList(model = it) { model ->
                Log.d("TAG", "Clicked on $model")
               // navController.navigate(route = NavScreens.DetailScreen.name + "/$model")

            }
        }
    }
    is Error -> printError(plantResponse.message)
}
}
}
@Composable
fun CardList(model: Plant, onItemClick:(String) -> Unit = {} ){

    Card(
        shape = MaterialTheme.shapes.small,
        modifier = Modifier
            .padding(
                bottom = 6.dp,
                top = 6.dp,
                start = 6.dp,
                end = 6.dp,
            )
            .clickable {
                onItemClick(model.id.toString())

            }
            .fillMaxWidth(),

        elevation = 8.dp

    ) {
        Column {
            Image(
                painter = rememberAsyncImagePainter(model = model.image) ,
                contentDescription = null,
                modifier = Modifier
                    .fillMaxWidth()
                    .height(125.dp),
                contentScale = ContentScale.Crop
            )

            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .padding(
                        top = 12.dp,
                        bottom = 12.dp,
                        start = 8.dp,
                        end = 8.dp
                    )
            ) {
                Text(
                    text = model.name.toString(),
                    modifier = Modifier
                        .fillMaxWidth(0.85f)
                        .wrapContentWidth(Alignment.Start),
                    style = MaterialTheme.typography.h5
                )
            }
            Text(
                text = "Author : ${model.room_location}",
                modifier = Modifier
                    .fillMaxWidth(0.85f)
                    .wrapContentWidth(Alignment.Start)
                    .padding(
                        top = 12.dp,
                        bottom = 12.dp,
                        start = 8.dp,
                        end = 8.dp
                    ),


                style = MaterialTheme.typography.h6
            )

        }
    }
}

问题现象 #

调整代码后出现不熟悉的Hilt相关错误，除此之外无其他报错，甚至Log.d("Data:","${user}")也没有输出调试信息，怀疑问题出在AppModule配置上，需要排查指导。

内容的提问来源于stack exchange，提问作者MayWheather