为啥自动创建的 NSManagedObject 子类没有“正确”标题？

Posted 2023-03-04

【中文标题】为啥自动创建的 NSManagedObject 子类没有“正确”标题？

【英文标题】：Why Automatically Created NSManagedObject Subclass do not have "Proper" header?为什么自动创建的 NSManagedObject 子类没有“正确”标题？

【发布时间】：2011-05-16 10:34:44

【问题描述】：

如果我创建了 NSManagedObject Subclass 的子类，我会在实现文件 Business.m 上看到这些函数（例如）

这些函数都没有在头文件 Business.h 中声明。我必须亲自添加

- (void)addDistrictsObject:(District *)value;
- (void)addCategoriesObject:(Category *)value;
- (void)addReviewsObject:(Review *)value;

我想知道为什么我必须手动添加这些声明？为什么我尝试生成子类时不自动生成？

顺便说一下功能：

- (void)addPromotionsObject:(Promotion *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Promotions"] addObject:value];
    [self didChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removePromotionsObject:(Promotion *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Promotions"] removeObject:value];
    [self didChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addPromotions:(NSSet *)value     
    [self willChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Promotions"] unionSet:value];
    [self didChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removePromotions:(NSSet *)value 
    [self willChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Promotions"] minusSet:value];
    [self didChangeValueForKey:@"Promotions" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];




- (void)addCategoriesObject:(Category *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Categories" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Categories"] addObject:value];
    [self didChangeValueForKey:@"Categories" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removeCategoriesObject:(Category *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Categories" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Categories"] removeObject:value];
    [self didChangeValueForKey:@"Categories" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addCategories:(NSSet *)value     
    [self willChangeValueForKey:@"Categories" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Categories"] unionSet:value];
    [self didChangeValueForKey:@"Categories" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removeCategories:(NSSet *)value 
    [self willChangeValueForKey:@"Categories" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Categories"] minusSet:value];
    [self didChangeValueForKey:@"Categories" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];




- (void)addImagesObject:(Image *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Images" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Images"] addObject:value];
    [self didChangeValueForKey:@"Images" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removeImagesObject:(Image *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Images" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Images"] removeObject:value];
    [self didChangeValueForKey:@"Images" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addImages:(NSSet *)value     
    [self willChangeValueForKey:@"Images" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Images"] unionSet:value];
    [self didChangeValueForKey:@"Images" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removeImages:(NSSet *)value 
    [self willChangeValueForKey:@"Images" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Images"] minusSet:value];
    [self didChangeValueForKey:@"Images" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];




- (void)addReviewsObject:(Review *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Reviews"] addObject:value];
    [self didChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removeReviewsObject:(Review *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Reviews"] removeObject:value];
    [self didChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addReviews:(NSSet *)value     
    [self willChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Reviews"] unionSet:value];
    [self didChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removeReviews:(NSSet *)value 
    [self willChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Reviews"] minusSet:value];
    [self didChangeValueForKey:@"Reviews" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];



- (void)addURLsObject:(URL *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"URLs" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"URLs"] addObject:value];
    [self didChangeValueForKey:@"URLs" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removeURLsObject:(URL *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"URLs" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"URLs"] removeObject:value];
    [self didChangeValueForKey:@"URLs" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addURLs:(NSSet *)value     
    [self willChangeValueForKey:@"URLs" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"URLs"] unionSet:value];
    [self didChangeValueForKey:@"URLs" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removeURLs:(NSSet *)value 
    [self willChangeValueForKey:@"URLs" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"URLs"] minusSet:value];
    [self didChangeValueForKey:@"URLs" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];




- (void)addDistrictsObject:(District *)value     
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Districts" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Districts"] addObject:value];
    [self didChangeValueForKey:@"Districts" withSetMutation:NSKeyValueUnionSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)removeDistrictsObject:(District *)value 
    NSSet *changedObjects = [[NSSet alloc] initWithObjects:&value count:1];
    [self willChangeValueForKey:@"Districts" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [[self primitiveValueForKey:@"Districts"] removeObject:value];
    [self didChangeValueForKey:@"Districts" withSetMutation:NSKeyValueMinusSetMutation usingObjects:changedObjects];
    [changedObjects release];


- (void)addDistricts:(NSSet *)value     
    [self willChangeValueForKey:@"Districts" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Districts"] unionSet:value];
    [self didChangeValueForKey:@"Districts" withSetMutation:NSKeyValueUnionSetMutation usingObjects:value];


- (void)removeDistricts:(NSSet *)value 
    [self willChangeValueForKey:@"Districts" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];
    [[self primitiveValueForKey:@"Districts"] minusSet:value];
    [self didChangeValueForKey:@"Districts" withSetMutation:NSKeyValueMinusSetMutation usingObjects:value];

【问题讨论】：

好问题，期待看到答案。我自己也有同样的疑惑。总是假设它是代码模板的过度站点。

【参考方案1】：

在 Xcode 4.x 之前，自动生成的代码确实会为方法生成标头定义。标头的丢失可能是 X4 非苹果式质量控制的另一个受害者。

标题实际上只需要智能感知或其他一些人机界面工具。 @dynamic 预处理器命令将告诉编译器这些方法基于命名约定而存在。在运行时，Core Data 将通过向实例化对象发送respondsToSelector 来检查类，否则它将使用直接键值方法。

您始终可以使用手动运行或构建的小脚本自行添加它们。这很痛苦，但显然 X4 设计专注于管理大型多产品项目，他们将球放在了一些较旧的基本东西上。

【讨论】：

现在问题似乎已经解决了。

【参考方案2】：

接口方法只需要用于静态类型检查并且只在编译时使用，如果方法调用是在运行时动态创建的，那么接口方法声明不会做任何事情。

【讨论】：

是的，我的程序如何知道 Business 类支持 addDistrictsObject:？智能感知不起作用。