我已经将所有相关代码添加到App Delegate,并且能够添加到数据模型并从application ationDidFinishLaunchingWithOptions中的数据模型获取.
我的问题出现在我试图写入View Controller中的数据模型时.我已将此代码添加到头文件中:
NSFetchedResultsController *fetchedResultsController;
NSManagedObjectContext *managedObjectContext;
@property (nonatomic, retain) NSFetchedResultsController *fetchedResultsController;
@property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;
并将此代码添加到我的实现文件中:
NSManagedObjectContext *context = [self managedObjectContext];
NSManagedObject *model = [NSEntityDescription
insertNewObjectForEntityForName:@"Events"
inManagedObjectContext:context];
[model setValue:@"Sample Event" forKey:@"eventName"];
NSError *error;
if (![context save:&error]) {
NSLog(@"Couldn't save: %@", [error localizedDescription]);
}
但是,我得到以下错误:
'NSInvalidArgumentException', reason: '+entityForName: nil is not a legal NSManagedObjectContext parameter searching for entity name 'Events''
有人知道是怎么回事吗?任何帮助都将不胜感激.