Question

I am watching a somewhat cruel behaviour momentarily: I have a ViewController for building a View programmatically. For this purpose I have stored the names of the UILabels that will be displayed in a NSDictionary that is held in an external class which is a singleton.
Unfortunately the NSDictionary is not accessible if I want to use the values in loadView. So I made some tests: The NSDictionary and its contents are availbale in init and the class is, of course, NSCFDictionary. If I have a look at it in loadView the class sometimes is NSCFDictionary and sometimes also CALayer or NSString?! I absolutely don’t know what is happening??? This is the code I use:

- (id) init
{
    self = [super initWithNibName:nil bundle:nil];    
    if (self)
    {
        UITabBarItem *tbi = [self tabBarItem];
        [tbi setTitle:@"xxx"];
    }

    NSEnumerator *num = [[[ValueDispatcher dispatcher] labelDic] keyEnumerator];
    NSLog(@"Class(init): %@", [[[ValueDispatcher dispatcher] labelDic] class]);
    NSLog(@"No: %i", [[[ValueDispatcher dispatcher] labelDic] count]);
    for (id key in num)
    {
        NSLog(@"Key %@  Value  %@", key, [[[ValueDispatcher dispatcher] labelDic] valueForKey:key]);
    }

       return self;
    }  

- (void)loadView 
{
    NSLog(@"Class(loadview)1: %@", [[[ValueDispatcher dispatcher] labelDic] class]);
    NSLog(@"No: %i", [[[ValueDispatcher dispatcher] labelDic] count]);
    NSEnumerator *num = [[[ValueDispatcher dispatcher] labelDic] keyEnumerator];
    for (id key in num)
    {
        NSLog(@"Key34 %@  Value  %@", key, [[[ValueDispatcher dispatcher] labelDic] valueForKey:key]);
    }
...

At which point between init and loadView can or will a NSDictionary be changed?
Btw, another info that might be important: If I use the above code and the NSDictionary is filled by an external service everything works fine. But if I fill the NSDictionary from a stored plist during startup it fails and I watch the described behaviour…

Answer 1

If I have a look at it in loadView the class sometimes is NSCFDictionary and sometimes also CALayer or NSString?

this (typically) means you have a reference count issue or you have not unregistered your observers correctly — assuming you never set the dictionary. run instruments with zombies enabled.

At which point between init and loadView can or will a NSDictionary be changed?

a lot can happen in that time beyond the code you posted.