https://github.com/lokming/QuestionBank在实体中访问1:N关系的问题
我有实体:Bank,Section,Subsection,Set,Question。 我有在实体部分访问的关系“的NSSet分段”和获取消息的问题:从该代码中 CRSectionVC.m填充一个的tableview细胞
- (NSArray *)allQuestions
{
NSSortDescriptor *division = [NSSortDescriptor sortDescriptorWithKey:@"subdivision" ascending:YES];
return [_section2.thesubsection sortedArrayUsingDescriptors:@[division]];
}
“[的UITableViewCell thesubsection]无法识别的选择发送到实例”我可以使用此代码
NSSortDescriptor *division2 = [NSSortDescriptor sortDescriptorWithKey:@"division" ascending:YES];
return [self.detailItem2.thesection sortedArrayUsingDescriptors:@[division2]];
_section2在CRSubsectionVC.h宣布然而访问银行实体的“NNSet部分”关系 @property(强,非原子)第*第2节;
故事板是 1. CRMasterViewController其显示从银行实体 '类别' 属性成的tableview,
Bank.h
@class Section;
@interface Bank : NSManagedObject
@property (nonatomic, retain) NSString * category;
@property (nonatomic, retain) NSSet *thesection;
@end
Bank.m
@implementation Bank
@dynamic category;
@dynamic thesection;
@end
当我一个轻按 '类别' 我原因请看并将一个Bank对象传递给CRDetailViewController。我使用以下代码:
NSSortDescriptor * division2 = [NSSortDescriptor sortDescriptorWithKey:@“division”ascending:YES]; return [self.detailItem2.thesection sortedArrayUsingDescriptors:@ [division2]];
如果我一个轻按“部分””我原因请看并传递一个节目的是CRSubsectionVC命名_section2。当我尝试访问NSSet *时,使用代码
NSSortDescriptor * division = [NSSortDescriptor sortDescriptorWithKey:@“subdivision”ascending:YES]来获取'subdivision'属性。 return [_section2.thesubsection sortedArrayUsingDescriptors:@ [division]];
从bank中获取节段关系(NSSet * thesection)'division'属性到tableview中。
Section.h
@class Bank, Subsection;
@interface Section : NSManagedObject
@property (nonatomic, retain) NSString * division;
@property (nonatomic, retain) Bank *bank;
@property (nonatomic, retain) NSSet *thesubsection;
@end
Section.m
@implementation Section
@dynamic division;
@dynamic bank;
@dynamic thesubsection;
@end
我得到错误[UITableViewCell thesubsection]:无法识别的选择器发送到实例。我无法弄清楚为什么自动访问器的“影响”工作正常,但不是“分段”。
Subsection.h
@class Section, Set;
@interface Subsection : NSManagedObject
@property (nonatomic, retain) NSString * subdivision;
@property (nonatomic, retain) Section *section2;
@property (nonatomic, retain) NSSet *set;
@end
Subsection.m
@implementation Subsection
@dynamic subdivision;
@dynamic section2;
@dynamic set;
@end
“_section2”声明在哪里,你在哪里给它赋值? – 2014-11-04 17:18:59
_section2在CRSubsectionVC.h中声明我已经添加了故事板如何与实体进行交互以使问题更清晰。 – Lok 2014-11-05 03:55:15