UILabel(CALayer) is leaking in ARC?

Question

I stuck in a problem, checked out many answers for a few days. My problem is when i choose profile>Leaks in Xcode, i see UILabel(CALayer) is always getting bigger in Live Bytes. Is it normal or is it a leak? what can i do about it? It is getting bigger when i change class and back to class which has these labels. Its like they are allocating over and over again but not release old ones.

i set my labels in h. file like that

@property(weak,nonatomic)IBOutlet UILabel *lblNumbersSpelling1;
@property(weak,nonatomic)IBOutlet UILabel *lblNumbersSpelling2;
@property(weak,nonatomic)IBOutlet UILabel *lblNumbersSpelling3;
@property(weak,nonatomic)IBOutlet UILabel *lblNumbersSpelling4;

and ,

- (void)viewDidUnload
{
    [super viewDidUnload];

    self.lblNumbersSpelling1=nil;
    self.lblNumbersSpelling2=nil;
    self.lblNumbersSpelling3=nil;
    self.lblNumbersSpelling4=nil;
    self.lblRecordSayfasiNot=nil;
   // Release any retained subviews of the main view.
}

i did that and i m not sure if it is necessary what i did in viewDidUnload method. I use Xcode 5. Thanks in advance.

you don't have to if you're using ARC, but additionally you need to release/reload when receive memory warning in your controller. — Jacek Grygiel, Dec 02 '13 at 13:07
@fenk There is no warning, i cleaned them up but labels are getting bigger in instruments section of Xcode. I dont know if it is a leak or what. thanks for reply by the way. — Yucel Bayram, Dec 02 '13 at 13:09
Are you using `ARC`? If so you don't need to do `self.lbl.... = nil;` If you're not using `ARC` then you don't do this in `viewDidUnload` it needs to be done in `dealloc` but I would recommend moving to using `ARC` Apple are really starting to push developers to use it also in my opinion it makes life a lot easier. — Popeye, Dec 02 '13 at 13:36
No need to do that then. Your label objects will be release automatically this is the purpose of `ARC` it is an Automated Memory Management System. — Popeye, Dec 02 '13 at 13:45
thank you, yes i agree about that but do you have an idea why it's look like getting bigger in profile? — Yucel Bayram, Dec 02 '13 at 13:52

NSDmitry · Answer 1 · 2013-12-02T14:02:34.477

2

viewDidUnload is deprecated in iOS6 and later.

Probably you want do this:

- (void)dealloc
{
    _lblNumbersSpelling1=nil;
    _lblNumbersSpelling2=nil;
    _lblNumbersSpelling3=nil;
    _lblNumbersSpelling4=nil;
    _lblRecordSayfasiNot=nil;
}

edited Dec 02 '13 at 14:02

answered Dec 02 '13 at 13:07

NSDmitry

460
5
12

Thanks i m checking it out. It is weird Xcode does not give any warning about viewDidUnload method is deprecated!! – Yucel Bayram Dec 02 '13 at 13:29
1

As the user has now indicated that they are using `ARC` they will not be able to use `dealloc` as this never gets called when using `ARC`. @yucelbayram I've just checked using xcode 5 and you are right there is no deprecation warning even though it has definitely been deprecated. I also checked in a version of xcode before 5 and it does have the deprecation warning this could be a bug in xcode 5 but trust the docs that `ProFFeSSor` has provided it is definitely deprecated. – Popeye Dec 02 '13 at 13:48
Yes i have no doubt about that anymore, this method deprecated. thanks – Yucel Bayram Dec 02 '13 at 13:53
5

@Popeye dealloc certainly does get called under ARC. You can't call it yourself, or call super, but dealloc is still executed. – jrturton Dec 02 '13 at 13:54
According to Apple's documentation, "you shouldn’t use accessor methods to set an instance variable ... in initializer methods and dealloc." So consider rewriting `self.foo = nil` as `_foo = nil`. – jlehr Dec 02 '13 at 13:57
@jrturton I will stand corrected but I was under the impression that when using `ARC` although `dealloc` may get called in the background I can't go adding something like `- (void)dealloc { NSLog(@"dealloc"); self.lblNumbersSpelling1=nil; }` which is what I meant. Is that correct or could I still call this sort of thing because I have tried and the `NSLog` doesn't get printed. – Popeye Dec 02 '13 at 13:58
5

@Popeye Incorrect. You can, and in many situations *must*, override `dealloc` in ARC-compiled code. However `dealloc` implementations under ARC cannot call `[super dealloc]`. If your `dealloc` method isn't being executed, your object is probably leaked (or cached indefinitely). – jlehr Dec 02 '13 at 14:00
@jlehr that is definitely good to know I will review my own code now thanks. – Popeye Dec 02 '13 at 14:04
I'm sorry, forget about `[super dealloc]`. Thank you for your comment! – NSDmitry Dec 02 '13 at 14:05
1

Based on the chosen answer on http://stackoverflow.com/questions/14501115/do-i-need-use-dealloc-method-with-arc I would say there is no need for dealloc method at all in this case. – Popeye Dec 05 '13 at 08:43

score 2 · Accepted Answer · answered Jun 06 '15 at 23:28

I experienced the same problem with my application with UILabel(CALayer) increasing in memory usage in Xcode's profile tool. At the end of the day, UILabel(CALayer) increasing in memory ended up being a symptom of a memory leak caused by another issue (specifically a strong reference to a delegate).

I would check the following to make sure another is issue isn't causing the UILabel(CALayer) to be retained:

Invalidate any NSTimers
Remove any observers to NSNotificationCenter
Make sure you are using weak references to self in blocks
Make sure that any delegate properties use weak references

Source: http://www.reigndesign.com/blog/debugging-retain-cycles-in-objective-c-four-likely-culprits/

I had this situation in a few projects, I am sure about first and second. But third and fourth make sense. Thanks i will try this in next time and i ll let you know the result. — Yucel Bayram, Jun 08 '15 at 06:17

UILabel(CALayer) is leaking in ARC?

2 Answers2