Problem accessing properties

[Anulith]

Hello all and thanks in advance for taking the time to help me out. I'm pretty new to objective-c and am having trouble with notification handlers. I have a object that registers itself as an observer of a notification. The notification is fired and I can access the object that fired the notification from my observer function just fine but I can't access any properties of self. Everytime I try to I get a bad selector or bad access error.

I have this same problem whether trying to access properties from the touch event handler or my own custom event handler. Below is my init and observer code.

- (id) initWithPlayerType : (PlayerType) type
{
	if((self = [super init]))
	{
		//initialize
		_playerType = type;
		_hand = [NSMutableArray array];
		switch(_playerType)
		{
			case PLAYER:
				_partner = PARTNER;
				isTouchEnabled = YES;
				[[NSNotificationCenter defaultCenter]
				 addObserver:self
				 selector:@selector(cardPlayed:)
				 name:@"cardPlayed"
				 object:nil ];
				break;
			case OPPONENT_1:
				_partner = OPPONENT_2;
				break;
			case PARTNER:
				_partner = PLAYER;
				break;
			case OPPONENT_2:
				_partner = OPPONENT_1;
				break;
			default:
				break;
		}
	}
	return self;
}

- (void) cardPlayed: (NSNotification *) notification
{
	NSLog(@"Card Played:");
	[[notification object] logValue];
        //the next line is where the exception is always thrown
	int handCount = [_hand count];
	for(int i=0; i<handCount; i++)
	{
		if([[_hand objectAtIndex:i] compare:[notification object]] == 0)
		{
			[_hand removeObjectAtIndex:i];
			break;
		}
	}
        //this is my original code that was giving me problems so 
        //I tried to do the above
	//[_hand removeObject:[notification object]];
	[self adjustCardPositions];
}

Am I missing something about how all this works? Do I not have access to the properties of the observer object because it goes out of scope somehow?

[Kalimba]

I think the issue may be with this line of code:

		_hand = [NSMutableArray array];

I believe this is assigning an autoreleased array instance to your '_hand' member, so when you attempt to access it later, it's no longer really there. Try changing that line to:

		_hand = [[NSMutableArray array] retain];
// or
		_hand = [[NSMutableArray alloc] init];
// or even
		_hand = [NSMutableArray new];

[Anulith]

Thank you! After adding the 'retain' it worked as desired. Why is the NSMutableArray object freed even though the Player object is still alive and holds a reference to the _hand array? I suppose I don't understand the garbage collector of objective c well enough.

Once again, thanks for your insight.