Question

I want to use a static class variable to maintain state of a Playlist object which will be shared between multiple classes in my app.

I make a call to getPlaylist in my AppDelegate, so that invokes my initialize class method and sets up the MSMutableArray.

However when I invoke addItemToPlaylist, the content variable is no longer the static instance of NSMutableArray. Instead it points to a totally different address in memory- a different address each time I debug.

Am I doing anything obviously wrong? Thanks in advance.

#import "Playlist.h"
static NSMutableArray *content;

@implementation Playlist

+ (void)initialize
{
    content = [NSMutableArray arrayWithCapacity:10]; 
}

+ (NSMutableArray *)getPlaylist
{
    if ([content count] == 0)
        return nil;

    return content;
}  

+ (void)addItemToPlaylist:(PlaylistTrack *)track; 
{
    [content addObject:track];
}

Answer 1

[NSMutableArray arrayWithCapacity] returns an auto-released object (there should be a complaint at runtime about there being no current auto-release pool).

Use [[NSMutableArray alloc] initWithCapacity] instead and add a class method to release it when done.

EDIT: Cheers @Lvsti.