Android Room无法确定如何将此字段保存到数据库中
我尝试通过room持久性库将值保存到数据库。我的Android Room无法确定如何将此字段保存到数据库中,android,kotlin,typeconverter,android-room,Android,Kotlin,Typeconverter,Android Room,我尝试通过room持久性库将值保存到数据库。我的设置Value Model Converter错误-缺少某些内容。如何以最佳方式保存设置skeycontract对象 日志: SettingsModel Error:(14, 1) error: Cannot figure out how to save this field into database. You can consider adding a type converter for it. 代码: object SETTING_CO
设置Value Model Converter
错误-缺少某些内容。如何以最佳方式保存设置skeycontract
对象
日志:
SettingsModel
Error:(14, 1) error: Cannot figure out how to save this field into database. You can consider adding a type converter for it.
代码:
object SETTING_CONS{
const val TABLE = "Content_Setting"
const val ID = "uid"
const val KEY = "key"
const val VALUE = "value"
}
class SettingsValueModel(var value: SettingsKeyContract)
class SettingsValueModelConverter {
@TypeConverter
fun fromString(value: String): SettingsKeyContract = Gson().fromJson(value, object : TypeToken<SettingsKeyContract>() {}.type)
@TypeConverter
fun fromModel(value: SettingsKeyContract): String = Gson().toJson(value)
}
@Entity(tableName = SETTING_CONS.TABLE)
class SettingsModel(@ColumnInfo(name = SETTING_CONS.KEY) @SETTINGS var key: String,
@ColumnInfo(name = SETTING_CONS.VALUE) var value: SettingsValueModel) {
@ColumnInfo(name = SETTING_CONS.ID)
@PrimaryKey(autoGenerate = true)
var uid: Int = 0
}
@Dao
interface SettingsDao {
@Query("SELECT * FROM ${SETTING_CONS.TABLE} WHERE ${SETTING_CONS.ID} = :key")
fun get(@SETTINGS key: String): LiveData<SettingsModel>
@get:Query("SELECT * FROM ${SETTING_CONS.TABLE}")
val all: LiveData<MutableList<SettingsModel>>
@Insert(onConflict = OnConflictStrategy.REPLACE)
fun insert(model: SettingsModel): Long
@Insert(onConflict = OnConflictStrategy.REPLACE)
fun insertAll(vararg models: SettingsModel): LongArray
@Query("DELETE FROM ${SETTING_CONS.TABLE} WHERE ${SETTING_CONS.KEY} = :key")
fun delete(@SETTINGS key: String)
@Query("DELETE FROM ${SETTING_CONS.TABLE}")
fun clear()
}
interface SettingsKeyContract { val key: String }
interface TypeSettingsKeyContract<out T : Any> : SettingsKeyContract { val default: T }
sealed class SETTING(override val key: String) : SettingsKeyContract {
object FIRST_LAUNCH_DATE : SETTING("first_launch_date"), TypeSettingsKeyContract<Long> { override val default = 0L }
}
对象设置\u CONS{
const val TABLE=“内容设置”
const val ID=“uid”
const val KEY=“KEY”
const val VALUE=“VALUE”
}
类设置值模型(变量值:SettingsKeyContract)
类设置值模型转换器{
@类型转换器
fromString(值:String):SettingsKeyContract=Gson().fromJson(值,对象:TypeToken(){}.type)
@类型转换器
fromModel(值:SettingsKeyContract):String=Gson().toJson(值)
}
@实体(表名=设置参数表)
类设置模型(@ColumnInfo(name=SETTING_CONS.KEY)@SETTINGS变量KEY:String,
@ColumnInfo(名称=设置值)变量值:设置值模型){
@ColumnInfo(名称=设置图标ID)
@PrimaryKey(自动生成=真)
变量uid:Int=0
}
@刀
接口设置DAO{
@查询(“从${SETTING\u CONS.TABLE}中选择*,其中${SETTING\u CONS.ID}=:key”)
乐趣获取(@SETTINGS-key:String):LiveData
@get:Query(“SELECT*FROM${SETTING_CONS.TABLE}”)
val all:LiveData
@插入(onConflict=OnConflictStrategy.REPLACE)
趣味插页(型号:SettingsModel):长
@插入(onConflict=OnConflictStrategy.REPLACE)
fun insertAll(vararg型号:SettingsModel):LongArray
@查询(“从${SETTING_CONS.TABLE}中删除,其中${SETTING_CONS.KEY}=:KEY”)
趣味删除(@SETTINGS key:String)
@查询(“从${SETTING_CONS.TABLE}删除”)
趣味十足
}
接口设置skeycontract{val key:String}
接口类型SettingsKeyContract:SettingsKeyContract{val默认值:T}
密封类设置(覆盖值键:字符串):设置SkeyContract{
对象首次启动日期:设置(“首次启动日期”),类型设置SKEYCONTRACT{override val default=0L}
}
您在哪里定义数据库?
您应该可以选择指定要使用的转换器,例如:
@Database(entities = arrayOf(SettingsModel::class) , version = 1, exportSchema = false)
@TypeConverters(SettingsValueModelConverter::class)
abstract class AppDatabase: RoomDatabase() {
abstract fun SettingsDao(): SettingsDao
}
你解决了吗?