Question

我有两个RLMObject名为RCRealmUser和RCRealmLocation。 RCRealmUser在RCRealmLocation上定义了一对一关系，RCRealmLocation与RCRealmUser呈反比关系。这就是我如何定义这两个：

RCRealmUser.h

@interface RCRealmUser : RLMObject

@property NSNumber <RLMInt> *userId;
@property NSString *username;
@property NSNumber <RLMInt> *countryCode;
@property NSNumber <RLMDouble> *phoneNumber;
@property NSString *fullName;
@property NSString *profileImageURL;
@property RCRealmLocation *location;

- (id)initWithMantleModel:(RCUserProfile *)user;

@end

RLM_ARRAY_TYPE(RCRealmUser)

RCRealmUser.m

@implementation RCRealmUser

+ (NSString *)primaryKey {
    return @"userId";
}

+ (NSArray *)indexedProperties {
    return @[@"fullName"];
}

+ (NSDictionary *)defaultPropertyValues {
    return @{@"countryCode": @91};
}

- (id)initWithMantleModel:(RCUserProfile *)user {
    self = [super init];
    if(!self) return nil;

    self.userId = user.userId;
    self.username = user.username;
    self.countryCode = user.countryCode;
    self.phoneNumber = user.phoneNumber;
    self.fullName = user.fullName;
    self.profileImageURL = user.profileImageURL.absoluteString;
    self.location = [[RCRealmLocation alloc] initWithMantleModel:user.location];

    return self;
}

@end

RCRealmLocation.h

@interface RCRealmLocation : RLMObject

@property (readonly) RLMLinkingObjects *userId;
@property NSNumber <RLMDouble> *latitute;
@property NSNumber <RLMDouble> *longitude;
@property NSDate *timestamp;
@property NSNumber <RLMInt> *accuracy;

- (id)initWithMantleModel:(RCLocation *)location;

@end

RLM_ARRAY_TYPE(RCRealmLocation)

RCRealmLocation.m

@implementation RCRealmLocation

+ (NSArray<NSString *> *)indexedProperties {
    return @[@"timestamp"];
}

+ (NSDictionary<NSString *,RLMPropertyDescriptor *> *)linkingObjectsProperties {
    return @{@"userId": [RLMPropertyDescriptor descriptorWithClass:RCRealmUser.class propertyName:@"userId"]};
}

- (id)initWithMantleModel:(RCLocation *)location {
    self = [super init];
    if(!self) return nil;

    self.latitute = location.latitute;
    self.longitude = location.longitude;
    self.timestamp = location.timestamp;
    self.accuracy = location.accuracy;

    return self;
}

现在当我尝试插入RCRealmUser时遇到错误

＆＃39; RLMException＆＃39;，原因：＆＃39;架构验证因以下原因而失败   错误：


Property＆＃39; userId＆＃39;声明为链接对象属性的来源＆quot; userId＆＃39;不是链接。＆＃39;

我在某处做错了吗？

Answer 1

“链接对象”属性必须表示链接（关系）。

在您的情况下，您说RCRealmLocation.userId属性应该代表通过其RCRealmUser属性链接到该位置的userId个对象。但是，RCRealmUser.userId与RCRealmLocation个对象不是关系，它是一个可选的整数。

我相信你想要的是RCRealmLocation上的一个属性，该属性引用链接到该位置的所有RCRealmUser及其locations关系。您可以通过将RCRealmLocation.userId属性更改为此来完成此操作：

@property (readonly) RLMLinkingObjects *users;

以及您对linkingObjectsProperties的实施：

return @{@"users": [RLMPropertyDescriptor descriptorWithClass:RCRealmUser.class propertyName:@"location"]};

阅读Realm's docs on inverse relationships了解详情。

架构验证失败：声明为链接对象属性的源的属性不是链接

1 个答案: