Android Room Persistence库TypeConverter未知问题

Question

我很难将我的实体保存到房间持久性数据库中。据我所知，RPL（RoomPersistenceLibrary）将只接受基元类型，因此我需要使用Typeconverters将我的两个字段:Calendar MstartDate、Calendar MendTime转换为字符串（这两个文件都用于设置开始和结束日期--每次创建WeekViewEvent，请参见构造函数）。

你知道我可能做错了什么吗？提前感谢您的任何帮助！：）

WeekViewEvent.class：

@Entity
public class WeekViewEvent implements Serializable {

@NonNull
@PrimaryKey
private long mId;
private String mName;
private String mLocation;
private int mColor;
private boolean mAllDay;
private Shader mShader;
private String Identifier;

@TypeConverters({WeekViewEventCONVERTER.class})
private Calendar mStartTime;
@TypeConverters({WeekViewEventCONVERTER.class})
private Calendar mEndTime;


public WeekViewEvent(long id, String name, String location, String identifier, int color, int startYear, int startMonth, int startDay, int startHour, int startMinute, int endYear, int endMonth, int endDay, int endHour, int endMinute) {
    this.mId = id;
    this.mStartTime = Calendar.getInstance();
    this.mStartTime.set(Calendar.YEAR, startYear);
    this.mStartTime.set(Calendar.MONTH, startMonth - 1);
    this.mStartTime.set(Calendar.DAY_OF_MONTH, startDay);
    this.mStartTime.set(Calendar.HOUR_OF_DAY, startHour);
    this.mStartTime.set(Calendar.MINUTE, startMinute);
    this.mEndTime = Calendar.getInstance();
    this.mEndTime.set(Calendar.YEAR, endYear);
    this.mEndTime.set(Calendar.MONTH, endMonth - 1);
    this.mEndTime.set(Calendar.DAY_OF_MONTH, endDay);
    this.mEndTime.set(Calendar.HOUR_OF_DAY, endHour);
    this.mEndTime.set(Calendar.MINUTE, endMinute);
    this.mName = name;
    this.Identifier = identifier;
    this.mLocation = location;
    this.mColor = color;}
...
}

 @TypeConverter
public static Calendar fromString (String value){
    Type calendarType = new TypeToken<Calendar>() {}.getType();
    return new Gson().fromJson(value, calendarType);
}

@TypeConverter
public static String fromCalendar (Calendar mStartTime){
    Gson gson = new Gson();
    String json = gson.toJson(mStartTime);
    return json;
}

}

和WeekViewEventDAO：

@Dao
public interface WeekViewEventDAO {

@Insert(onConflict = OnConflictStrategy.REPLACE)
public long insertWeekViewEvent (WeekViewEvent event);

@Update(onConflict = OnConflictStrategy.REPLACE)
public void updateWeekViewEvent (WeekViewEvent event);

@Delete
public void deleteWeekViewEvent (WeekViewEvent event);

@Query("DELETE FROM WeekViewEvent")
public void deleteAllWeekViewEvents();

@Query("SELECT * FROM WeekViewEvent")
WeekViewEvent getWeekViewEvent();

@Query("SELECT * FROM WeekViewEvent")
public List<WeekViewEvent> getAllWeekVieweventsList();}

Answer 1

我认为您的问题是您没有用于此字段的类型转换器：

private Shader mShader;

尝试添加@ignore将其标记为非持久性。