我设立了一个非核心数据项目。 我现在要使用核心数据。 在建设阶段,我把我的双手与核心数据库联系起来。 在我的申请代表方法中,我想人工地创造像这样管理下的物体环境。
NSManagedObjectContext *aContext = [[NSManagedObjectContext alloc] init];
当我做上述工作时,我有以下错误:
Receiver NSManagedObjectContext for class message is a forward declaration.
Any suggestions on what I might be doing wrong?
您在申请代表档案中需要进口核心数据/核心数据。
#import <CoreData/CoreData.h>
由于你可能通过外部申请加以使用,你应将它列入预先编造的头号档案,阁下:
#ifdef __OBJC__
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>
#endif
Just write #import < CoreData/CoreData.h > in your implementation file. It will work
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