Why is Apple's documentation that getting a ManagedObjectContext from a UIApplicationDelegate bad?

Question

Curious why ManagedObjectContexts should be passed to UIViewControllers when they are created, and not just grabbing them from UIApplicationDelegate?

The docs say this makes your applications tougher, but I see no nuances about when to use the template.

Thank!

Answer 1

Imagine that I ask you to do some kind of task, for example, to paint a room. If I just say “go paint the room”, you need to ask me a lot of questions, for example:

• Which room?
• Where is the paint?
• Where are the brushes?
• ?

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Answer 2

, dependency injection UIViewControllers , UIApplication, .

MVC:

• Model

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Answer 3

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, Core Data , , . - , . , ; Cource Student, . , Core Data, . :

@interface Cource (StudentAccess)
-(NSArray*)studentsStortedByName;
@end

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@interface Cource (CourceAccess)
+(Cource*)caurceByID:(NSString*)courceID;
+(NSArray*)allCources;
+(NSArray*)courcesHeldByTeacher:(Teacher*)teacher;
@end

. . , CourceViewController StudenViewController, Core Data , , :

 -(id)initWithManagedObjectContext:(NSManagedObjectContext*)moc
                           student:(Student*)student;

:

 -(id)initWithStudent:(Student*)student;

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Answer 4

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