android - e : [kapt] An exception occurred: java. lang.IllegalArgumentException:intcannot be converted to an Element

Question

我正在尝试在我的 android 应用程序中实现 Room。我正在尝试从 API 获取数据并将它们保存在本地数据库中。但是当我运行应用程序时出现了这个错误

e: [kapt] An exception occurred: java.lang.IllegalArgumentException:intcannot be converted to an Element

这是我的数据库类:

@Database(entities = [
    (User::class)],
        version = 1, exportSchema = false)
abstract class UserDatabase : RoomDatabase() {


    abstract fun userDao(): UserDao

    companion object {

        @Volatile
        private var INSTANCE: UserDatabase? = null

        fun getDatabase(context: Context): UserDatabase {

            if (INSTANCE == null){
                synchronized(this){
                    INSTANCE = Room.databaseBuilder(
                            context.applicationContext,
                            UserDatabase::class.java,
                            "user_database")
                            .build()
                }
            }
            return INSTANCE!!
        }
    }


}

这是我的存储库:

class Repository(application: Application) {


    private var mUserDao: UserDao

init {
        val db = UserDatabase.getDatabase(application)


    }
    @WorkerThread
    fun createUser(user: User) {
        mUserDao.createUser(user)
    }

    @WorkerThread
    fun deleteUser(id: Int) {
        mUserDao.deleteUser(id)
    }

    @WorkerThread
    fun getUser(id: Int) {
        mUserDao.getUser(id)
    }

这是我的 userDao

@Dao
interface UserDao{

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    fun createUser(user: User)

    @Delete
    fun deleteUser(int: Int)

    @Query("SELECT * FROM user WHERE user_id = :userID")
    fun getUser(userID: Int): LiveData<User>

}

我的登录 View 模型:

class LoginViewModel(application: Application) : AndroidViewModel(application) {

    var repository: Repository = Repository(application)


    fun createUser(user: User) = repository.createUser(user)

}

也发生了这个错误:

org.gradle.api.tasks.TaskExecutionException: Execution failed for task':app:kaptDebugKotlin' <30 internal calls> atjava.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)atjava.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)<1internal call> at java.lang.Thread.run(Thread.java:745) Caused by:org.gradle.api.GradleException: Compilation error. See log for moredetails atorg.jetbrains.kotlin.gradle.tasks.TasksUtilsKt.throwGradleExceptionIfError(tasksUtils.kt:16)atorg.jetbrains.kotlin.gradle.internal.KaptWithKotlincTask.compile(KaptWithKotlincTask.kt:79)<17internal calls> ...33 more

Answer 1

问题出在你的@Delete

@Delete
fun deleteUser(int: Int)

应该是什么

@Delete
fun deleteUser(user: User)

@Delete 方法的参数应该是实体或实体数组，而不是Int