Question

I’m trying to share an NSArray object between several different view controllers and my first thought was to add a property on the app delegate as they all have access to this object.

But after some debugging it appears I can’t actually share this array for some reason. When I set the object from the first view controller and NSLog the results all is well. But when I attempt to get that array value using another view controller object it always returns UITouchData (not the value previously shown in the logs after my first view controller set the value)

Here is the code that I’m using to set the value

NSArray* cookies = [NSHTTPCookie 
                    cookiesWithResponseHeaderFields:[response allHeaderFields] 
                    forURL:[NSURL URLWithString:@""]];

  [appDelegate setAuthCookie:cookies];

Here is part of the .h for my app delegate

@interface SomeAppDelegate : NSObject <UIApplicationDelegate> {
  NSArray* authCookie;
}

@property (retain) NSArray* authCookie;

- (void)setAuthCookie:(NSArray *)cookie;
- (NSArray *)getAuthCookie;

@end

Here is the .m for the methods in question

@synthesize authCookie;

- (void)setAuthCookie:(NSArray *)cookie
{
  authCookie = cookie;  
}

- (NSArray *)getAuthCookie
{
  return authCookie;
}

Here is the attempt to grab this array in the second view controller that fails (technically it doesn’t fail on this line but I don’t get an NSArray back as expected so when I try to use this it fails)

NSArray* cookies = [appDelegate getAuthCookie];

Any way I can share state using the app delegate like this?

Answer 1

Your memory management is wrong, and you are getting a completely different object which has inherited the old array’s address when you later use the getter.

Your @property is correct, but you’ve written your own setter and getter that do not retain the object. You don’t need to use both @property/@synthesize and supply your own getter/setter. The former is a newer means of automating the latter.

If you remove your implementations of setAuthCookier: and getAuthCookie then your code should work.