NSMutableArray of names from NSDictionaries in an NSDictionary

[r@t]

Hi, I am having trouble making an array of objects (employee names) from a group of NSDictionaries (individual employee records) inside another NSDictionary *dictionary (personnel). The key for each sub Dictionary is an employee ID.

I might well be coming at this from a completely wrong direction, as i am very much a newbie, but i have got as far as getting a pName from each sub Dictionary, all be it fleetingly. I just can't get the pNames added into MutableArray *names.

any help or guidance would be greatly appreciated ...

                NSMutableArray *names;
                NSArray *keys;
		int i, count;
		id key, value;
		
		keys = [dictionary allKeys];
		count = [keys count];
		for (i = 0; i < count; i++)
		{
			key = [keys objectAtIndex: i];
			value = [dictionary objectForKey: key];
			NSLog (@"value:%@", value); 
				
			NSString *pName = [value objectForKey:@"personName"];
			NSLog (@"pName:%@", pName);// the debugger shows the correct pName string with each loop
				
			[names addObject:pName];
		}
			NSLog (@"names:%@", names);// in the debugger names (null)

[smasher]

I don't see you pointing the names pointer at an NSMutableArray - you declared the pointer variable but never created an object for it to point to

                NSMutableArray *names;
                NSArray *keys;
		int i, count;
		id key, value;
		
                names = [NSMutableArray array]; //setting names here
		keys = [dictionary allKeys];
		count = [keys count];
		for (i = 0; i < count; i++)
		{
			key = [keys objectAtIndex: i];
			value = [dictionary objectForKey: key];
			NSLog (@"value:%@", value); 
				
			NSString *pName = [value objectForKey:@"personName"];
			NSLog (@"pName:%@", pName);// the debugger shows the correct pName string with each loop
				
			[names addObject:pName];
		}
	NSLog (@"names:%@", names);

Now it should work, but I'll go you two better. First with some fast enumeration:

                NSMutableArray *names = [NSMutableArray array];        
		NSArray *values = [dictionary allValues];
		for (id value in values)
		{
			NSString *pName = [value objectForKey:@"personName"];
			[names addObject:pName];
		}
	NSLog (@"names:%@", names);

Or better yet, some key-value coding:

        
	NSArray *values = [dictionary allValues];
		
	NSArray *names = [values valueForKey:@"personName"];

	NSLog (@"names:%@", names);

Names is not mutable in the last example, but you could call mutableCopy on it if you need to.

-- Society for the Elimination of most Loops