We've got an app that's fairly large now, and we recently upgraded to iOS 10. In doing so, a new bug was introduced, and we're at a loss for how to solve it.
The crash itself occurs during a call to layoutIfNeeded(). However, the crash does not occur unless the layoutIfNeeded() call is contained inside a UIView.animateWithDuration() block. No amount of weak referencing, delays, or dispatch calls seems to have any effect. The same crash can be triggered during a call to [super viewWillTransitionToSizeWithTransitionCoordinator].
"An Objective-C message was sent to a deallocated 'Bubble' object (zombie) at address: 0x10924f030."
Enabling Zombies shows that we have a Release call going to one of our UIView subclasses, which we've named Bubble. Nothing too special there, some layout constraints and a gesture recognizer.
The Instruments app hasn't helped much, nor has the new visual memory debugger in Xcode 8 (though it is awesome, surprisingly little documentation on the feature).
I've included a screenshot of Zombies during the crash here. While I know the retain count can be misleading, there are certainly some confusing points to the trace, and we could really use some help diagnosing this.
Again, this code worked fine before iOS 10. We've been unable to find any notes from Apple about underlying changes to UIKit that may have had an effect.
Some more brief info: [Bubble cleanBubbles] simply iterates over the subviews of any view passed in, and removes the subview if its a Bubble class.
Apologies on certain violations of naming conventions, I'm sure there's plenty to criticize!
Thanks
Related
I use 100% programmatic constraints in my interface code. Upgraded to Xcode 13 and iOS 15. Got tons of NEW execution warnings about constraints, all saying that the system had to break some constraints to comply with others. I had not seen such warnings for several years, and have not touched my constraint code in all that time. Yet thorough testing shows my code continues to run correctly. What's up?
Answer: I had been a bit cavalier with the timing of when iOS actually calculated the constrained dimensions. I put all of my programmatic interface declarations into a single method. At the bottom of that method, I have long had code that went beyond interface layout, into NavCon preliminaries. Among those NavCon declarations, I had lines like:
self.view_D0_Tutorial.frame = self.view_CenterPane_D0_Tutorial.frame;
I noted at the time that I wrote and debugged those lines, that using the debugger to ask what the location data was, all I ever got was CRect (0,0,0,0), yet the code somehow did the right thing.
Well, in the upgrade, iOS apparently changed the way they do things. I had to do two things in response.
(1) moved all the NavCon preliminary code to a new separate method, and call it with performSelector and 0 delay.
(2) changed the simple frame assignment to a more limited assignment:
self.view_D0_Tutorial.frame = CGRectMake(0, 0, self.view_CenterPane_D0_Tutorial.frame.size.width, self.view_CenterPane_D0_Tutorial.frame.size.height);;
The combination made the error messages go away, and my code continues to run correctly!
I keep getting EXC_BAD_ACCESS(code=1) intermittently. I've been trying to figure out what's wrong with this exception for hours but I have not been able to get to the bottom of it. The problem is that XCode doesn't really tell why it's crashing.
I have All Objective-C Exceptions set up with po $arg1 but the crash pointer still points to AppDelegate. Just to give you guys more info of what I am doing, I am creating dashboard with a pretty customized NSOutlineView that calls reloadData pretty frequently (every 5 seconds). The dataSource also gets updated before reloadData is called. I have suspicion that this concurrent updating of data and redisplaying it might be the issue but I am still not 100%.
When it crashes, it points to class AppDelegate: NSObject, NSApplicationDelegate.
The stackframe looks like:
When I click on frame 1, I get:
And the debug navigator
I have a UITextView, and whenever I click on it, the app crashes with the following error:
-[__NSSetM _hideForKeyboardAppearance]: unrecognized selector sent to instance 0x7fb8aa76cd60
If I run the app multiple times, it always crashes at the same place, but the intercepting object that is throwing the "unrecoginzed selector" can be different. Sometimes it is UIImage instead of NSSetM, sometimes, it is a UIConstraint, etc.
Even if I don't assign the UITextView to a specific outlet in my class, or have it assigned to a delegate, I get the same behavior. This happens on both simulator and hardware.
Any ideas what is going on?
p.s. this is iOS 8. Crash happens on both iPhone and iPad.
Edit: Note that this happens even though the UITextView calls no code. I removed any outlet connections in the storyboard, and even made it so my class doesn't implement UITextViewDelegate. Still crashes. That is why I am so puzzled and wondered if anyone has ever encountered something like this. One thing to note is that the view controller having this issue is buried several screens deep within a UISplitViewController. Not sure if someone UI elements buried deep in the nav stack are somehow intercepting the keyboard call?
I have an iPhone app, that seems to have memory leaking problem. It's a puzzle game, after a few puzzles, the app crashes on devices.
I'm now trying to use xcode Instruments to detect what's going on. First time to use Instruments.
I noticed a leak bar in the "Leaks" plot, right the time when the view is loaded:
What are these memory leaking objects, detected by xCode Instruments?
. However these leaked objects are small, so I guess my app has other problems.
When my app continues to run, usually for 10+ rounds on an iPad 2, it then crashes. I don't much about Instruments yet, so I watch "All Heap Allocations". At the beginning of first round puzzle, the column "# Overall" is ~70k, it grows slowly between rounds of puzzles. When a new round puzzle comes in, it goes to ~90k, then round by round it reaches ~200k, then crashes.
Before crashes, in the log console I see memory warning and "CONNECTION INTERRUPTED".
I've followed a few things after searching memory leaking, such set NSArray/NSDictionary or mutable ones to nil, as much as possible (although not all of them, since some go between puzzles). I also changed UIImage imageNamed to [UIIMage alloc] initWithContentOfFile.
What else should I look/check to see what causes memory problem? TIA!
EDIT:
I wish I could post some codes that may be the suspect, but I really don't know what part to post. I should've check via Instruments in the course developing, so that I would know what caused the problem.
Regarding other view controllers. I do have others (menu, settings, app-store-rate, etc) and I generated all of them via code. My app doesn't have a storyboard or nib file. When I test crashes, I just click Next Puzzle button, so all other views will not show at all. So, before crash, the only view shown is the main view, with a few button, a few subviews, an animated pictures (but only the first puzzle as introduction). If it helps, here is my app:
http://itunes.apple.com/us/app/wordsect/id599455449?ls=1&mt=8
If you trying to debug application with Instruments - enable zombie detection mode:
In
Xcode: Product->Scheme->Edit Scheme
Select Debug scheme
Select Arguments tab bar on the scheme description
In Environments variables add and check NSZombieEnabled variable
Then when you start application under Instruments control, you'll get name of the instance, when your application crashed.
i'm currently working on an ios project with some people, one of us decided to use ARC in a part of the app.
Unfotunatly, we are currently experiencing some crashes when coming back from background.
Here are the steps we follow to crash the application, we perform them with the ios-simulator:
start the application
get on a ViewController A (coded with ARC)
get on a ViewController B (not coded with ARC -to be honest i don't
know if it's relevant-)
put the application in background.
simulate a memory warning (thx to the simulator)
start again the application, we'll be on the ViewController B
go back on the Viewcontroller A
the application crashes pointing the main function with an
EXC_BAD_ACCESS
We did try to use NSZombieEnabled to YES, but when we do it, the application doesn't crash and keeps running perfectly, so we wonder if it might be possible that NSZombieEnabled doesn't work well with ARC?
if anyone could give me a quick and clear insight about ARC and NSZombieEnabled that would be apreciated, i think i know how all of it works, but apparently i must be missing something.
Thanks anyway for your help and time.
Better than using the NSZombieEnabled, you should Profile the project, and use the Zombie instrument. When you do the same thing it should stop and say "zombie messaged", where you can click an arrow to see the class that is a zombie, and where it was allocated/deallocated.
I don't think the crash has to do with ARC, instead in viewDidUnload you are deallocating something, and then not setting a reference to nil - when you come back it tries to use the invalid reference.
Probably you would be better off if everything used ARC as it really helps to cure issues like this (the bug is very likely in the non-ARC code).