有一个CoreData中的一对多关系。现在想从coredata实体中创建一个对象,然后设置为NSSet。
我想实例化对象没有错,但是再设置NSSet时就不对。
AppDelegate *appDelegate = [[UIApplication sharedApplication]delegate];
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSSet *selectedCategories = [NSSet set];
for (NSString *categoryName in self.categories /*NSMutableArray propterty*/) {
Category *category = [NSEntityDescription
insertNewObjectForEntityForName:@"Category" inManagedObjectContext:context];
category.name = categoryName;
[selectedCategories setByAddingObject:category];
}
[self.delegate addCategoryViewControllerDidSelectCategory:
self didSelectCategories:selectedCategories];