无法在我的测试应用程序中使用 Room 构建应用程序

Question

When I try to build the app it gives me an error

Execution failed for task ':app:kaptDebugKotlin'.
> A failure occurred while executing org.jetbrains.kotlin.gradle.internal.KaptWithoutKotlincTask$KaptExecutionWorkAction
   > java.lang.reflect.InvocationTargetException (no error message)

In build.gradle I specified

apply plugin: 'kotlin-kapt'

and

implementation "android.arch.persistence.room:runtime:1.1.1"
kapt 'android.arch.persistence.room:compiler:1.1.1'

My database class

@Database(entities = [WeatherOfCities::class], version = 1, exportSchema = false)
public abstract class AppDatabase : RoomDatabase(){
    public abstract fun weatherOfCitiesDao(): WeatherOfCitiesDao
    companion object {
        private var INSTANCE: AppDatabase? = null
        fun getDatabase(context: Context): AppDatabase {
            if (INSTANCE == null) {
                synchronized(this) {
                    INSTANCE =
                        Room.databaseBuilder(context, AppDatabase::class.java, "database")
                            .build()
                }
            }
            return INSTANCE!!
        }
    }
}

My entity class

@Entity
data class WeatherOfCities (
    @PrimaryKey(autoGenerate = true)
    val id: Long,
    val city: String,
    val weather: Int
)

My Dao interface

@Dao
interface WeatherOfCitiesDao {
    @Query("SELECT * FROM weatherOfCities")
    fun getAll(): List<WeatherOfCities>
    @Insert
    fun insert(weatherOfCities: WeatherOfCities)
    @Update
    fun update(weatherOfCities: WeatherOfCities)
}

And Build db in MainActivity

class MainActivity : AppCompatActivity(), MainView {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        var presenter = (application as MVPApplication).mainPresenter
        presenter?.attachView(this)
        var db = AppDatabase.getDatabase(this)
        var weatherOfCitiesDao = db.weatherOfCitiesDao()
    }
}

Why is the application not building and is it due to errors in the application code?

Answer 1

You need to add the ktx dependency eg

implementation 'androidx.room:room-ktx:1.1.1'

I'd also suggest using 2.4.1 for all the room dependencies rather than 1.1.1