Question

所以我有一些方法可以使用MagicalRecord在CoreData中保存我的设置。但后来我试图这样做，我收到了这个错误：Illegal attempt to establish a relationship 'settings' between objects in different contexts

所以这是我的代码：此方法是由特定用户保存数据，该用户现在正在使用programm

-(void)saveSettingsFirst:(BOOL)first{
    [MagicalRecord saveWithBlockAndWait:^(NSManagedObjectContext *localContext){
        SettingsData *newData = [self settingsDataForCurrentUserInContext:localContext];

        //SettingsData *newData = [SettingsData MR_createEntityInContext:localContext];
        newData.firstValue = @(first);
        NSLog(first ? @"saveSettings FIRST 0" : @"saveSettings FIRST 1");
        newData.settings = [[CacheManager shared] currentUserWithContext:localContext];

        NSLog(@"Settings one is saved");
    }];
}

此方法从CoreData为currentUser进行设置：

-(SettingsData*)settingsDataForCurrentUserInContext:(NSManagedObjectContext*)context{
    NSLog(@"In settingsDataForCurrentUserInContext");
    SettingsData *settings = [SettingsData MR_findFirstByAttribute:@"settings" withValue:[[CacheManager shared] currentUserWithContext:context]];
    return settings;
}

最后一个方法，从CoreData获取当前用户的userData：

-(UserData*)currentUserWithContext:(NSManagedObjectContext*)context{
    UserData *persons = [UserData MR_findFirstInContext:context];
    if (persons!=nil) {
        NSLog(@"Current user with context not nil value");
    }
    return persons;
}

我需要帮助才能认识到这是我的错误，因为对我而言，这似乎都是逻辑。

Answer 1

您在获取SettingsData时使用默认上下文。所以，改变：

SettingsData *settings = [SettingsData MR_findFirstByAttribute:@"settings" withValue:[[CacheManager shared] currentUserWithContext:context]];

为：

SettingsData *settings = [SettingsData MR_findFirstByAttribute:@"settings" withValue:[[CacheManager shared] currentUserWithContext:context] inContext: context];

（免责声明：在浏览器中输入，未针对拼写错误进行测试）

MagicalRecord和CoreData保存在不同的上下文错误中

1 个答案: