I don't know if I'm doing this properly. I'm working on a large application in which a user must log in and and interact with a variety of functionality and data. There are many view controllers that need to have access to this user object.
The following snippet is the moment when the user logs in and now I have a user object to use across my app. Just in this case I'm using dummy data.
User *user = [User new];
[user setupTempOfflineData];
self.newViewController.user = user;
[self containerAddChildViewController:self.newViewController];
In the newViewController is the property:
@property (nonatomic, strong) User *user;
Now NewViewController may have many children and those children have view controllers of their own. All of them given a strong reference to the user. Additional information such as a list of registered groups or content that the user had created remains as well. And sometimes I'll either access downloaded information via the user object, or just store and share references to the arrays/data themselves.
Something in my head is telling me I should be using a singleton or some other design pattern I'm just not familiar with. Thus bringing me here to ask the question:
Am I doing this right?
Edit: Informative link on KVO
What you're doing should work. Also have you thought about protocol and delegate? You may want to consider this design pattern in the event that you want the NewViewController (or other view controllers) to be notified when the User object has changed (KVO/Notificaiton are another design patterns).
User.h
@class User;
@protocol userProtocol <NSObject>
-(void) userObjectDidGetUpdated:(User*) u;
@end
@interface User:NSObject {}
@property (nonatomic,weak) id <userProtocol> delegate; // use weak here to prevent reference cycle
@end
User.m -- call notifyDelegatesUserObjectHasChanged when you want to notify the delegates to get the updated User object
@implementation
@synthesize delegate;
-(void) notifyDelegatesUserObjectHasChanged {
[[self delegate] userObjectDidGetUpdated:self];
}
@end
Now, you can register the view controller to get the updated User object as follow...
NewViewController.h
#import "User.h"
@interface NewViewController:UIViewController <userProtocol> {}
NewViewController.m
@implementation
-(void) userObjectDidGetUpdated:(User*) u {
// this callback method will get called when the User object changes
}
@end