Navigation Control Problem - objective-c

Question

I am using some methods to load a new .xib and go back to the main menu. However after about five time it crashes by using too much memory. I need to be able to go back to the main menu and to the game many times. Any other methods I should use for the navigation controls.
Main Menu part:
GameViewController* game = [[GameViewController alloc initWithNibName:#"GameViewController" bundle:nil];
[self.navigationController pushViewController:game animated:NO];
Game part to return to main menu:
[self.navigationController popViewControllerAnimated:NO];
Here is the viewdidLoad
{
- (void)viewDidLoad {
[super viewDidLoad];
[self StartTimer];
TotalSeconds = 0;
GameCenterTotalSeconds = 0;
timeSec = 0;
timeMin = 0;
Background = [[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 480, 320)] autorelease];
Background.image = [UIImage imageWithContentsOfFile:[ [ NSBundle mainBundle] pathForResource:#"Background" ofType:#"png"]];
[self.view addSubview:Background];
timeLabel.textColor = [UIColor redColor];
[self.view addSubview:timeLabel];
NumberLabel = [[[UIImageView alloc] initWithFrame:CGRectMake(0, -4, 60, 70)] autorelease];
NumberLabel.image = [UIImage imageWithContentsOfFile:[[ NSBundle mainBundle] pathForResource:#"Number" ofType:#"png"]];
[self.view addSubview:NumberLabel];
QuestionNumber = [[[UILabel alloc] initWithFrame:CGRectMake(23, 17, 20, 20)] autorelease];
QuestionNumber.text = #"1";
QuestionNumber.textColor = [UIColor redColor];
QuestionNumber.backgroundColor = [UIColor clearColor];
[QuestionNumber setFont:[UIFont fontWithName:#"Marker Felt" size:30]];
[self.view addSubview:QuestionNumber];
numberLives = 1;
appDelegate = (OppositeMoronTestAppDelegate *)[[UIApplication sharedApplication]delegate];
musicButton = [[[UIButton buttonWithType:UIButtonTypeCustom] retain] autorelease];
musicButton.frame = CGRectMake(5, 283, 35, 35);
musicButton.backgroundColor = [UIColor clearColor];
if (appDelegate.shouldPlayMusic == YES) {
UIImage *Image = [UIImage imageWithContentsOfFile:[[ NSBundle mainBundle] pathForResource:#"MusicOn" ofType:#"png"]];
[musicButton setBackgroundImage:Image forState:UIControlStateNormal];
[musicButton addTarget:self action:#selector(TurnMusicOff) forControlEvents:UIControlEventTouchUpInside];
} else {
UIImage *Image = [UIImage imageWithContentsOfFile:[[ NSBundle mainBundle] pathForResource:#"MusicOff" ofType:#"png"]];
[musicButton setBackgroundImage:Image forState:UIControlStateNormal];
[musicButton addTarget:self action:#selector(TurnMusicOn) forControlEvents:UIControlEventTouchUpInside];
}
[self.view addSubview:musicButton];
[self showQuestion1];
}
}

Answer 1

try autorelease on your view controller:
GameViewController* game = [[[GameViewController alloc initWithNibName:#"GameViewController" bundle:nil] autorelease];
The navigation controller will take ownership of the view controller passed to it, so you don't have to keep a reference to it. But you can't keep allocating GameViewControllers over and over without releasing them. autorelease is useful for that. You could also release it after you've passed it to the navigation controller if you prefer:
GameViewController* game = [[GameViewController alloc initWithNibName:#"GameViewController" bundle:nil];
[self.navigationController pushViewController:game animated:NO];
[game release];
game = nil;
EDIT:
So if you're already releasing the game object, then it must be a memory leak within the GameViewController class itself.
Annything you alloc, copy or retain in your GameViewController class you're supposed to release in the dealloc method (and maybe also in the viewDidUnload method if you're alloc/copy/retaining in the viewDidLoad method).
The iOS Memory Management Programming Guide might be helpful if you want to get into more detail.
If you want to post the relevant code from the GameViewController class, I'm sure someone will be able to help you pin down the memory leak.
You can also try the Leaks tool in Instruments
EDIT 2:
I'm assuming you have several IBOutlets connected to properties in your GameViewController class...
don't know if you're already doing this, but in your viewDidUnload method AND on your dealloc method you have to set all of these IBOutlets properties to nil in order to release them, like so:
- viewDidUnload
{
//... whatever comes before
self.timeLabel = nil;
self.NumberLabel = nil;
//... etc
}
- dealloc
{
//... whatever comes before
self.timeLabel = nil;
self.NumberLabel = nil;
//... etc
[super dealloc];
}
In general, if you have any properties declared with retain, that means that when you set that property the object will be retained. If you set that property to nil, the object that was there will be released for you. So any properties with the retain keyword should be set to nil (or the backing ivar released).