NSManagedObjectContext 问题

发布于 2024-09-16 10:09:28 字数 1484 浏览 3 评论 0原文

我已经使用“use coredata”选项集设置了我的项目。

XCode 显然会自动为我设置所有这些，现在我在应用程序委托头文件中有这些行：

@interface GFree2AppDelegate : NSObject <UIApplicationDelegate> {
    UIWindow *window;
    GFree2ViewController *viewController;
    UINavigationController *navController;

    NSManagedObjectContext *managedObjectContext_;
    NSManagedObjectModel *managedObjectModel_;
    NSPersistentStoreCoordinator *persistentStoreCoordinator_;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet GFree2ViewController *viewController;
@property (nonatomic, retain) IBOutlet UINavigationController *navController;

@property (nonatomic, retain, readonly) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, retain, readonly) NSManagedObjectModel *managedObjectModel;
@property (nonatomic, retain, readonly) NSPersistentStoreCoordinator *persistentStoreCoordinator;

- (NSString *)applicationDocumentsDirectory;

@end

我的第一个问题是，为什么托管对象和内容的初始指针有下划线？这就是它们在 .m 文件中的使用方式，但 @property 没有下划线。

我的下一个问题是，我想在我的脚本中进一步使用上下文，所以我使用了这些行：

GFree2AppDelegate *delegate = [[UIApplication sharedApplication] delegate];
context = delegate.managedObjectContext;

现在这不起作用，因为 obvs 没有 @synthesize。但我需要合成什么？我是否使用下划线进行合成，或者不使用下划线进行合成，我能得到它吗？ delegate.managedObjectContext 还是 delegate.managementObjectContext_？或者根本没有？哈..我不太确定我理解所有这些托管对象的东西。

多谢。汤姆

原文

I've set up my project with the "use coredata" option set.

XCode obviously set all this up for me automatically, and now I have these lines in the app delegate header file:

@interface GFree2AppDelegate : NSObject <UIApplicationDelegate> {
    UIWindow *window;
    GFree2ViewController *viewController;
    UINavigationController *navController;

    NSManagedObjectContext *managedObjectContext_;
    NSManagedObjectModel *managedObjectModel_;
    NSPersistentStoreCoordinator *persistentStoreCoordinator_;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet GFree2ViewController *viewController;
@property (nonatomic, retain) IBOutlet UINavigationController *navController;

@property (nonatomic, retain, readonly) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, retain, readonly) NSManagedObjectModel *managedObjectModel;
@property (nonatomic, retain, readonly) NSPersistentStoreCoordinator *persistentStoreCoordinator;

- (NSString *)applicationDocumentsDirectory;

@end

My first question is, why do the initial pointers for the managed object and stuff have underscores? This is how they are used in the .m file and yet the @propertys have no underscores.

My next question is, I want to use the context further in in my script so I've used these lines:

GFree2AppDelegate *delegate = [[UIApplication sharedApplication] delegate];
context = delegate.managedObjectContext;

Now this won't work because obvs there is not @synthesize. But what do I need to synthesize? Do I synthesize WITH the underscore, or without, and do I get it? delegate.managedObjectContext or delegate.managedObjectContext_? Or not at all? Ha.. I'm not too sure I understand all this managed object stuff.

Thanks a lot.
Tom

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