NSMutableDictionary添加和删除KVO

Question

我有一个关于KVO的快速问题.我理解,对于NSArray,如果需要观察添加,您可以执行以下操作.

 NSIndexSet* set = [NSIndexSet indexSetWithIndex:[someIndex integerValue]];
            [self willChange:NSKeyValueChangeInsertion valuesAtIndexes:set forKey:@"theArrayName"];
                // add the objects at the specified indexes here
            [self didChange:NSKeyValueChangeInsertion valuesAtIndexes:set forKey:@"theArrayName"];

注册观察后,您将获得一个更改字典,其中包含已更改的索引.

但是,我不明白如何观察NSMutableDictionary的新对象添加.有没有办法观察对象的添加/删除？

谢谢,

[编辑]我找到了满足我当前需求的解决方案.我希望以下内容有助于未来的开发人员.

[self willChangeValueForKey:@"someDictionary" withSetMutation:NSKeyValueUnionSetMutation usingObjects:[NSSet setWithObject:someObject]];

[Images setObject:someObject forKey:someIndex];

[self didChangeValueForKey:@"someDictionary" withSetMutation:NSKeyValueUnionSetMutation usingObjects:[NSSet setWithObject:someObject]];

Answer 1

只是为了确保这个问题得到解答。功劳归于@DoubleDunk

[self willChangeValueForKey:@"someDictionary" withSetMutation:NSKeyValueUnionSetMutation usingObjects:[NSSet setWithObject:someObject]];

    [Images setObject:someObject forKey:someIndex];

    [self didChangeValueForKey:@"someDictionary" withSetMutation:NSKeyValueUnionSetMutation usingObjects:[NSSet setWithObject:someObject]];