Home/ Questions/Q 7504817
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-29T21:41:57+00:00

In my app when I am switching views, after about the 4th time I

  • 0

In my app when I am switching views, after about the 4th time I switch views I get a crash that says:

*** -[CALayer retain]: message sent to deallocated instance 0x6c4ba0

I have NSZombieEnabled in Xcode and it points me to this line whenever it switches views:

[self.view removeFromSuperview];

Also if I do a backtrace of the (gdb) it gives me this:

#0  0x37dd68a0 in ___forwarding___ ()
#1  0x37d31680 in __forwarding_prep_0___ ()
#2  0x37d1d026 in CFRetain ()
#3  0x37d26bb2 in +[__NSArrayI __new::] ()
#4  0x37d26acc in -[__NSPlaceholderArray initWithObjects:count:] ()
#5  0x3518e680 in -[UIView(Hierarchy) _makeSubtreePerformSelector:withObject:withObject:copySublayers:] ()
#6  0x3518e7a4 in -[UIView(Hierarchy) _makeSubtreePerformSelector:withObject:withObject:copySublayers:] ()
#7  0x3534c40c in __UIViewWillBeRemovedFromSuperview ()
#8  0x3518dad0 in -[UIView(Hierarchy) removeFromSuperview] ()
#9  0x000368a6 in __block_global_1 (.block_descriptor=<value temporarily unavailable, due to optimizations>, finished=1 '\001') at /Users/bobsComputer/Desktop/Projects/NewApp/MyApp/MyApp3/MyApp3ViewController.mm:135
#10 0x351a70be in -[UIViewAnimationBlockDelegate _didEndBlockAnimation:finished:context:] ()
#11 0x351a181a in -[UIViewAnimationState sendDelegateAnimationDidStop:finished:] ()
#12 0x351a6fb8 in -[UIViewAnimationState animationDidStop:finished:] ()
#13 0x3354fba6 in CA::Layer::run_animation_callbacks ()
#14 0x37a91f7a in _dispatch_main_queue_callback_4CF$VARIANT$mp ()
#15 0x37da72dc in __CFRunLoopRun ()
#16 0x37d2a4dc in CFRunLoopRunSpecific ()
#17 0x37d2a3a4 in CFRunLoopRunInMode ()
#18 0x378a8fcc in GSEventRunModal ()
#19 0x351ba742 in UIApplicationMain ()

Also this how I switch views, I have a main view controller. I then use a ParentView and protocols to call these methods from my other views controllers. I then use custom UIView animations to switch views.

Does anyone have any ideas why this is crashing?

Thanks!

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    -[UIView addSubview:] causes the subview to be retained, and -[UIView removeFromSuperview] causes the view to be released. This is direct from Apple’s UIView documentation. At that point, one of your objects needs to retain the CALayer or it will be deallocated.

    I assumed that the CALayer was created by you directly. All UIViews are associated with CALayers; the CALayer is what a UIView draws into, and then its CALayer is composited onto the screen. If you’re not working with CALayers directly, this is a symptom of another problem.

    The core problem you’re describing is an overrelease. It’s possible you’re not retaining a UIView when you should. I suggest you run the Xcode analyzer (in Xcode 4, choose the Product > Analyze) menu item and see what gets reported. Pay special attention to all of the memory management errors it reports.

    • 0