Subviews and dealloc - am I an idiot?

[yezaev]

I've been coding for the iphone for nearly 9 months now, and I've always been under the impression that when a UIView instance is deallocated, each of its subviews is removed from it and sent the release message.
Something's come up and I'm wondering if I just dreamed that up.
Does this actually happen?

[BdR]

Good question, I wanted to ask the same thing. I guess there's no way to verify subviews being deallocated, except to watch Instruments app and see if memory use keeps rising..? Isn't there a better way to monitor this?

Anyway, here's my code example..

@interface MyTile : UIView {
	NSInteger theNumber;
}
@property (assign, nonatomic) NSInteger theNumber;

-(id)initWithFrame:(CGRect)frame andNumber:(int)aNumber;

and the code to initialise MyTile view

-(id)initWithFrame:(CGRect)frame andNumber:(int)aNumber {
	[super initWithFrame: frame];

	// load the image and resize it
	UIImageView *tmpImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tilegraphic.png"]];
	tmpImage.frame = CGRectMake(0, 0, frame.size.width, frame.size.height);

	// add image to view
	[self addSubview: tmpImage];
	[tmpImage release];

	// set number property
	self.theNumber = aNumber;
	
	// add label with text
	UILabel *tmpLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 32, 32)];
	tmpLabel.backgroundColor = [UIColor clearColor];
	[tmpLabel setTextAlignment:UITextAlignmentCenter];
	tmpLabel.text = @"123";
	
	// add labelview to imageview
	[self addSubview:tmpLabel];
	[tmpLabel release];

	// return pointer to self, for use outside this constructor method
	return self;
}

Now, when I'm done with the tiles from one game (each new game can have different tile dimensions etc.) I send a release to all of the MyTiles.

The question is: will the UIImageView ("tilegraphics.png") and the UILabel ("123") views also be released or will they cause a memory leak? If so, do I have to add a UIImageView and UILabel pointer to MyView class, just so I can send them a release-message in the MyTile dealloc?