我通过将逆设置为No inverse来解决这个问题，我不知道为什么，可能有Apple Bug。

我同意这里可能有漏洞。我已经修改了添加对象>setter的实现，以正确地追加到NSMutableOrderedSet。 - (void)addSubitemsObject:(SubItem *)value { NSMutableOrderedSet* tempSet = [NSMutableOrderedSet orderedSetWithOrderedSet:self.subitems]; [tempSet addObject:价值); 自我。subitems = tempSet; ｝ 将集合重新分配给self。子项将确保发送will /DidChangeValue通知>。

leell，你确定在这样的自定义设置NSMutableOrderedSet值存储在该集将被CoreData正确地保存到数据库吗?我没有检查，但它看起来像CoreData对NSOrderedSet一无所知，并期望NSSet作为多关系容器。

收到同样的错误，@LeeIII解决方案为我工作(谢谢!)。我建议稍微修改一下:

使用objective-c类别存储新方法(所以我们不会失去我们的方法，如果Item再次生成) 检查我们是否已经有了可变集合

Item+category.m的内容:

#import "Item+category.h"

@implementation Item (category)

- (void)addSubitemsObject:(SubItem *)value {
    if ([self.subitems isKindOfClass:[NSMutableOrderedSet class]]) {
        [(NSMutableOrderedSet *)self.subitems addObject:value];
    } else {
        NSMutableOrderedSet* tempSet = [NSMutableOrderedSet orderedSetWithOrderedSet:self.subitems];
        [tempSet addObject:value];
        self.subitems = tempSet;
    }
}

@end

我已经找到窃听器了。它发生在willChangeValueForKey:withSetMutation:usingObjects:中。

这个呼叫会触发一连串的通知，可能很难追踪，当然，一个回复者的变化可能会影响到另一个，我怀疑这就是为什么苹果什么都没做的原因。

然而，这在Set中是可以的，只有OrderedSet上的Set操作会发生故障。这意味着只有四个方法需要修改。因此，我所做的只是将Set操作转换为等效的Array操作。这些工作非常完美，开销最小(但必要)。

On a critical level, this solution does suffer from one critical flaw; if you are adding objects and one of the objects already exists, then it is either not added or moved to the back of the ordered list (I don't know which). In either case, the expected ordered index of the object by the time we arrive at didChange is different from what was anticipated. This may break some people's apps, but it doesn't affect mine, since I am only ever adding new objects or I confirm their final locations before I add them.

- (void)addChildrenObject:(BAFinancialItem *)value {
    if ([self.children containsObject:value]) {
        return;
    }
    NSIndexSet * indexSet = [NSIndexSet indexSetWithIndex:self.children.count];
    [self willChange:NSKeyValueChangeInsertion valuesAtIndexes:indexSet forKey:ChildrenKey];
    [[self primitiveValueForKey:ChildrenKey] addObject:value];
    [self didChange:NSKeyValueChangeInsertion valuesAtIndexes:indexSet forKey:ChildrenKey];
}

- (void)removeChildrenObject:(BAFinancialItem *)value {
    if (![self.children containsObject:value]) {
        return;
    }
    NSIndexSet * indexSet = [NSIndexSet indexSetWithIndex:[self.children indexOfObject:value]];
    [self willChange:NSKeyValueChangeRemoval valuesAtIndexes:indexSet forKey:ChildrenKey];
    [[self primitiveValueForKey:ChildrenKey] removeObject:value];
    [self didChange:NSKeyValueChangeRemoval valuesAtIndexes:indexSet forKey:ChildrenKey];
}

- (void)addChildren:(NSOrderedSet *)values {
    if ([values isSubsetOfOrderedSet:self.children]) {
        return;
    }
    NSIndexSet * indexSet = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(self.children.count, values.count)];
    [self willChange:NSKeyValueChangeInsertion valuesAtIndexes:indexSet forKey:ChildrenKey];
    [[self primitiveValueForKey:ChildrenKey] unionOrderedSet:values];
    [self didChange:NSKeyValueChangeInsertion valuesAtIndexes:indexSet forKey:ChildrenKey];
}

- (void)removeChildren:(NSOrderedSet *)values {
    if (![self.children intersectsOrderedSet:values]) {
        return;
    }
    NSIndexSet * indexSet = [self.children indexesOfObjectsPassingTest:^BOOL(id obj, NSUInteger idx, BOOL *stop) {
        return [values containsObject:obj];
    }];
    [self willChange:NSKeyValueChangeRemoval valuesAtIndexes:indexSet forKey:ChildrenKey];
    [[self primitiveValueForKey:ChildrenKey] minusOrderedSet:values];
    [self didChange:NSKeyValueChangeRemoval valuesAtIndexes:indexSet forKey:ChildrenKey];
}

当然，还有一个更简单的解决方案。内容如下;

- (void)addChildrenObject:(BAFinancialItem *)value {
    if ([self.children containsObject:value]) {
        return;
    }
    [self insertObject:value inChildrenAtIndex:self.children.count];
}

- (void)removeChildrenObject:(BAFinancialItem *)value {
    if (![self.children containsObject:value]) {
        return;
    }
    [self removeObjectFromChildrenAtIndex:[self.children indexOfObject:value]];
}

- (void)addChildren:(NSOrderedSet *)values {
    if ([values isSubsetOfOrderedSet:self.children]) {
        return;
    }
    [self insertChildren:values atIndexes:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(self.children.count, values.count)]];
}

- (void)removeChildren:(NSOrderedSet *)values {
    if (![self.children intersectsOrderedSet:values]) {
        return;
    }
    [self removeChildrenAtIndexes:[self.children indexesOfObjectsPassingTest:^BOOL(id obj, NSUInteger idx, BOOL *stop) {
        return [values containsObject:obj];
    }]];
}

如果你正在使用mogenerator，那么代替

[parentObject add<Child>sObject:childObject];

简单的使用方法:

[[parent object <child>sSet] addObject:childObject];

我发现使用LeeIII的方法是有效的，但在分析时发现它非常慢。解析1000个条目花了15秒。注释出代码以添加关系将15秒变成2秒。

我的解决方案(更快，但更丑陋)包括创建一个临时可变数组，然后在所有解析完成后将其复制到有序集中。(如果您要添加许多关系，这只是性能上的优势)。

@property (nonatomic, retain) NSMutableArray* tempItems;
 ....
@synthesize tempItems = _tempItems;
 ....

- (void) addItemsObject:(KDItem *)value 
{
    if (!_tempItems) {
        self.tempItems = [NSMutableArray arrayWithCapacity:500];
    }
    [_tempItems addObject:value];
}

// Call this when you have added all the relationships
- (void) commitRelationships 
{
    if (_tempItems) {
        self.items = [NSOrderedSet orderedSetWithArray:self.tempItems];
        self.tempItems = nil;
    }
}

我希望这能帮助到其他人!