在 Firebase 中存储/检索枚举的解决方法是什么？

Question

首先，我认为这是我的错，我在项目后期才开始使用Firebase。

无论如何，我想做的是将 Pub 对象存储到数据库中。它包含各种信息，例如开放时间，评级，设施等。

问题不在于存储，而是每当我尝试从数据库中获取酒吧列表时，我都会遇到此问题

这是错误。

 com.google.firebase.database.DatabaseException: Could not find enum value of com.example.matasolutions.pintindex.Day for value "Monday"
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.deserializeToEnum(com.google.firebase:firebase-database@@16.1.0:302)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.deserializeToClass(com.google.firebase:firebase-database@@16.1.0:212)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.deserializeToType(com.google.firebase:firebase-database@@16.1.0:178)

这是枚举类。

public enum Day {
    MONDAY,TUESDAY,WEDNESDAY,THURSDAY,FRIDAY,SATURDAY,SUNDAY
};

这就是带有枚举的构造函数的样子

public SingleOpeningHours(Day dayOfTheWeek,String openingTime, String closingTime){
        this.dayOfTheWeek = dayOfTheWeek;
        this.openingTime = openingTime;
        this.closingTime = closingTime;
    }

最后，这就是它被添加到列表然后添加到数据库的方式。

  ArrayList<SingleOpeningHours> singleOpeningHours = new ArrayList<SingleOpeningHours>();
        singleOpeningHours.add(new SingleOpeningHours(Day.MONDAY, "09:00", "00:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.TUESDAY, "09:00", "01:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.WEDNESDAY, "09:00", "01:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.THURSDAY, "09:00","01:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.FRIDAY, "09:00", "01:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.SATURDAY, "09:00", "01:00"));
        singleOpeningHours.add(new SingleOpeningHours(Day.SUNDAY, "09:00", "01:00"));

编辑：我有7个与正在存储的对象相关联的枚举类。最好的解决方法是什么？提前感谢伙计们

Answer 1

Firebase Database 不支持枚举数据类型。要查看有关支持的数据类型的详细信息，请查看支持的数据类型

解决方案1：(最简单的(只需使用天数字符串而不制作枚举

将星期几更改为字符串

String dayOfTheWeek; // Changed from Day to String
public SingleOpeningHours(String dayOfTheWeek,String openingTime, String closingTime){
    this.dayOfTheWeek = dayOfTheWeek;
    this.openingTime = openingTime;
    this.closingTime = closingTime;
}

并在单开时间列表中使用字符串，如下所示，

ArrayList<SingleOpeningHours> singleOpeningHours = new ArrayList<SingleOpeningHours>();
    singleOpeningHours.add(new SingleOpeningHours("MONDAY", "09:00", "00:00"));
    singleOpeningHours.add(new SingleOpeningHours("TUESDAY", "09:00", "01:00"));

解决方案 2：将 SingleOpenHours 对象中使用的 dayOfTheWeek 更改为字符串，并在 Enum 类中使用 name(( 方法将枚举值转换为字符串

String dayOfTheWeek; // Changed from Day to String
String openingTime;
String closingTime;
public SingleOpeningHours(Day dayOfTheWeek,String openingTime, String closingTime){
this.dayOfTheWeek = dayOfTheWeek.name(); // make sure add .name()
this.openingTime = openingTime;
this.closingTime = closingTime;

}

并在单打开时间列表中使用枚举日(此处没有变化(

ArrayList<SingleOpeningHours> singleOpeningHours = new ArrayList<SingleOpeningHours>();
singleOpeningHours.add(new SingleOpeningHours(Day.MONDAY, "09:00", "00:00"));
singleOpeningHours.add(new SingleOpeningHours(Day.TUESDAY, "09:00", "01:00"));

希望这些解决方案能帮助您解决问题