我遇到了一个问题,即当我尝试修改它时,核心数据在我的谓词中没有看到任何变化。我花了很多时间试图找出为什么我获取的属性没有向我显示正确的结果(请参见下面的代码),最后在又一次喝咖啡休息后,我看到(突然!)我获取的属性开始正常工作。更新数据模型是否有一些延迟?还是我应该更频繁地休息?
-(void)printData{
NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Empl"];
NSError *error;
NSArray *empls = [[self managedObjectContext] executeFetchRequest:request error:&error];
for (NSManagedObject *emplMO in empls){
NSString *output = [NSString stringWithFormat:@"%@ \n", [emplMO valueForKey:@"emplName"]];
[self.managedObjectContext refreshObject:emplMO mergeChanges:YES];
NSArray *allChairs = [emplMO valueForKey:@"allChairs"];
output = [output stringByAppendingFormat:@" has %d chairs \n", allChairs.count];
NSLog(@"%@", output);
}
}