i have a subclass of UIViewController, and when it is called from another class the app just freezes - i used the Xcode debugger and figured that when I'm trying to access the class's view property the app freeze. another weird thing is that when i type in the debugger control panel: "po objectOfTheProblematicClass.view" the debugger stops responding.
the code I used was similar to this:
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Main" bundle:[NSBundle mainBundle]];
WTStickyViewController *stickyVC = [sb instantiateViewControllerWithIdentifier:#"WTStickyViewController"];
stickyVC.sticky = sticky;
// Setup view controller containment:
[self.parentViewController addChildViewController:stickyVC];
self.containerView = self.parentViewController.view;
[self.containerView addSubview:stickyVC.view];
WTStickyViewController is the subclass of UIViewController. the app freezes when it reaches
[self.containerView addSubview:stickyVC.view];
but it's because this is the first time that stickyVC.view is called.
if for example i would put somewhere in the code
UIView *viewForExample = stickyVC.view;
the app would freeze there.
the exact same app works fine when compiled on a device with iOS 8 but has this problem with iOS 9.
if anyone knows why is this happening and if there is a solution it will be great. thank you.
I was having a similar issue and it was absolutely maddening. The CPU went to around 100% in the resource monitor during debug as the app deadlocked. Printing to console or just generally accessing the view controller's view property caused this behavior. Ultimately, what 'fixed' it for me was removing it from the base localization file. I know that doesn't make sense, but I'll elaborate as best as I can.
I'm maintaining a legacy universal app that has 2 'main' storyboards called Main_iPhone and Main_iPad, which as you can probably guess are the loaded dynamically based on what device you're launching on. I noticed that only the iPhone nib view was deadlocking as described, and iPad was loading fine. The only thing I could tell as that the iPhone storyboard had localization enabled while the iPad storyboard had not. So here's the steps I took loosely to remove it from base localization (you may want to do this in a separate branch/sandbox to make sure this works before deleting project references):
Right click the problematic view and/or storyboard in question, show in finder. For me it was inside the Base.lproj folder as expected.
[Re]move the file to a different directory so Xcode can not find the link the project (file goes red in file browser). Press delete to remove the file from the project file's reference from the project itself.
Add the file back at the new location in your repository/project structure so Xcode picks it up as a new file. Ensure all of your references to the file are updated to the new location.
Verify your storyboard/xib file is not localized anymore, clean project, re-run and see if the issue is still there (see image).
You can also just update the file location using the update location button in the file properties view on the right side (see other image).
Don't know if this will fix it, but I thought I'd share what helped me in the chance that it helps others as well.
A bug report was sent to apple and hopefully it will be fixed soon - the problem is indeed with Xcode 7.
If you are encountering a similar problem, it can be solved by doing one of the following:
1) Use Xcode 6.4, at least until apple fixes this bug.
2) Rebuild the problematic view in the storyboard.
I will post the radar link once I got a chance to speak with my manager about it...
I am very new to this. I followed Apple's tutorial step by step for the iPhone project "HelloWorld". I ran it in the iPhone 5.0 simulator and it crashed:
2012-11-02 14:46:06.782 HelloWorld[9880:c07] * Terminating app due
to uncaught
exception 'NSInvalidUnarchiveOperationException', reason: 'Could not instantiate
class named NSLayoutConstraint'
* First throw call stack:
(0x14a2052 0xea2d0a 0x144aa78 0x144a9e9 0x32f7d7 0x32f9af 0x32f6b7 0x23036d 0xd7e2c 0xd83a9 0xd85cb 0x38a73 0x38ce2 0x38ea8 0x3fd9a
0x10be6 0x118a6 0x20743 0x211f8 0x14aa9 0x138cfa9 0x14761c5 0x13db022
0x13d990a 0x13d8db4 0x13d8ccb 0x112a7 0x12a9b 0x1fed 0x1f15 0x1)
terminate called throwing an exception(lldb)
Can someone please tell me what went wrong? I'm using Xcode 4.5.
By default, when you create a new iOS project in Xcode 4.5, your storyboard or XIB is set to use Autolayout, which is a new feature in iOS 6.0. The NSLayoutConstraint class is part of the Autolayout system, and it doesn't exist in older versions of iOS.
If you want to deploy your app to an older version of iOS, you need to change your storyboard or XIB to not use Autolayout. It's a checkbox in the File Inspector:
Your Xib file (Interface builder file) contains AutoLayout elements, which iOS 5 does not support.
In Xcode, go to your .xib file(s), and for each one, turn off AutoLayout. There should be a checkbox on the left hand side saying "Use AutoLayout", uncheck it and try again. (This is under the first tab in the left hand side inspector, when you have File's owner) selected.
I stumbled into this error when I was working on an older project I wanted to update. I had selected the "Use Autolayout" checkbox to start working with constraints, but had forgotten to update my Deployment Target setting to iOS 6.
You need to run it in iPhone 6.0 simulator. Your error:
* Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: 'Could not instantiate class named NSLayoutConstraint' *
Suggests that you are using autolayout, which only works on iOS 6.
When testing in the iOS6 simulator, I am getting the following error when clicking a disclosure indicator:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIViewController _loadViewFromNibNamed:bundle:] was unable to load a nib named "LocationDetail"'
It runs perfectly fine in iOS5.
I do NOT have the LocationDetail nib anymore, nor need to use it. I have looked in my entire project for references to it, as well as in my MainWindow nib and all connections looking to see where it could be used, but I find none.
How would XCode still be wanting to load this, and why only the errors in iOS6?
The problem is not in Xcode, but in the iOS Simulator. If you've removed all references to the .xib in your project, and cleaned everything as you described, the problem is that the .xib file still exists in the app bundle in the Simulator. You should try deleting the app from the Simulator (or better yet, Reset All Content & Settings on the Simulator). This will fix it.
what i know is that initWithStyle:UITableViewStyleGrouped will call the initWithNibName:Bundle: method...
your class had the same name as your nib file, so when you called the initWithStyle:UITableViewStyleGrouped it tried to load that nib file.
when you renamed your class, it didn't find an nib with the same class name so no errors showed up as before.
I decided to just rename my class and .h and .m files and that fixed the issue.
Who knows why.
My project built and ran completely fine. (it's rootViewController is a TabBarController) So I added two new view controller to my storyboard and connected them to my rootviewcontroller. In storyboard, the tabs were added just fine and everything looked okay. So I added the ViewController classes to my project and hooked them up to the correct viewControllers in storyboard. However, when I ran the project my new tabs were not visible in the simulator. So I ran "clean" on my project, deleted my application out of the simulator, reset the simulator to its original settings, and my new tabs still would not appear in the simulator. So i quit everything and restarted my mac. This time, when I ran my project it gave me the "Thread 1:signal SIGABRT" So i became frustrated and deleted my new viewControllers, both from the storyboard and the classes menu. I sent the classes to trash. But STILL I get the SIGABRT error. Even now that I am back to my original project, I am getting the error. I can't figure out what is wrong. Since it won't let me post a picture of my screen, just let me know if you need any additional debugger output or anything.
this is what its giving me in the debugger.
2012-07-05 09:22:33.336 NewsomeBand[265:15203] ***
Terminating app due to uncaught exception
'NSInvalidArgumentException', reason: 'Could not
find a storyboard named 'MainStoryboard' in bundle
NSBundle </Users/tammyscheele/Library/Application
Support/iPhone Simulator/5.1/Applications/
1B3E088D-23A6-4B77-8CBB-390A9720818A/
NewsomeBand.app> (loaded)'
*** First throw call stack:
(0x152b022 0x30d2cd6 0x5179f2 0xecd60 0xecff8 0xec17f 0xfb183 0xfbc38 0xef634
0x16beef5 0x14ff195 0x1463ff2 0x14628da 0x1461d84 0x1461c9b
0xebc65 0xed626 0x202d 0x1f95)
terminate called throwing an exception(lldb)
From the debugger output that you posted it looks like you may have accidentally also deleted a reference to your main/root story board. I'm guessing this based on
'NSInvalidArgumentException', reason: 'Could not
find a storyboard named 'MainStoryboard' in bundle
Either that or did you accidentally rename it somewhere or misspell it? It looks like its something simple in any case.
I solved it! I went into the info tab inside my project and set "Main storyboard file base name" to "MainStoryboard", and also made sure that my storyboard was named "MainStoryboard". That seemed to fix everything
I created a button and added an action for it, but as soon as it invoked, I got this error:
-[NSCFDictionary numberButtonClick:]: unrecognized selector sent to instance
0x3d03ac0 2010-03-16 22:23:58.811
Money[8056:207] *** Terminating app
due to uncaught exception
'NSInvalidArgumentException', reason:'*** -[NSCFDictionary numberButtonClick:]: unrecognized selector sent to instance 0x3d03ac0'
This is my code:
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
UIButton *numberButton = [UIButton buttonWithType:UIButtonTypeCustom];
numberButton.frame = CGRectMake(10, 435, 46, 38);
[numberButton setImage:[UIImage imageNamed:#"one.png"] forState:UIControlStateNormal];
[numberButton addTarget:self action:#selector(numberButtonClick:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview: numberButton];
}
return self;
}
-(IBAction)numberButtonClick:(id)sender{
NSLog(#"---");
}
It looks like you're not memory managing the view controller properly and it is being deallocated at some point - which causes the numberButtonClicked: method to be sent to another object that is now occupying the memory that the view controller was previously occupying...
Make sure you're properly retaining/releasing your view controller.
For those getting here via Google like I did, which probably pertains more to Xcode 4.2+/iOS 5+ more, what with ARC. I had the same error "unrecognized selector sent to instance". In my case I had a UIButton's target action set up to pass itself as the sender parameter, but later realised I didn't need it and removed that in code. So, something like:
- (IBAction)buttonPressed:(UIButton *)sender {
Was changed to:
- (IBAction)buttonPressed {
Right clicking the UIButton in question showed that the Touch Up Inside event was associated with the view controllers buttonPressed: method. Removing this and reassigning it to the modified method worked a treat.
This was the top Google answer for this issue, but I had a different cause/result - I thought I'd add in my two cents in case others stumble across this problem.
I had a similar issue just this morning. I found that if you right click the UI item giving you the issue, you can see what connections have been created. In my case I had a button wired up to two actions. I deleted the actions from the right-click menu and rewired them up and my problem was fixed.
So make sure you actions are wired up right.
OK, I have to chip in here. The OP dynamically created the button. I had a similar issue and the answer (after hours of hunting) is so simple it made me sick.
When using:
action:#selector(xxxButtonClick:)
or (as in my case)
action:NSSelectorFromString([[NSString alloc] initWithFormat:#"%#BtnTui:", name.lowercaseString])
If you place a colon at the end of the string - it will pass the sender. If you do not place the colon at the end of the string it will not, and the receiver will get an error if it expects one. It is easy to miss the colon if you are dynamically creating the event name.
The receiver code options look like this:
- (void)doneBtnTui:(id)sender {
NSLog(#"Done Button - with sender");
}
or
- (void)doneBtnTui {
NSLog(#"Done Button - no sender");
}
As usual, it is always the obvious answer that gets missed.
In my case the function was not expecting an argument but the button was configured to send one causing the error. To fix this I had to rewire the event handler.
Here is my function:
Notice it contains no arguments.
Here is an image of my button configuration (right click on the button to view it):
Notice there are 3 event handlers.
To fix this I had to remove each of the event items since one of them was sending a reference to itself to the enterPressed function. To remove these items I clicked on the little x icon next to the name of each item until there were no items shown.
Next I had to reconnect the button to the event. To do this hold down the Control key and then drag a line from the button to the action. It should say "Connect Action". Note: I had to restart XCode for this to work for some reason; otherwise it only let me insert actions (aka create a new action) above or below the function.
You should now have a single event handler wired to the button event that passes no arguments:
This answer compliments the answer by #Leonard Challis which you should read as well.
This can also happen if you don't set the "Class" of the view in interface builder.
In my case, I was using NSNotificationCenter and was attempting to use a selector that took no arguments, but was adding a colon. Removing the colon fixed the problem.
When using a selector name, don't use a trailing colon if there are no arguments. If there's one argument, use one trailing colon. If there are more than one argument, you must name them along with a trailing colon for each argument.
See Adam Rosenfield's answer here: Selectors in Objective-C?
I had this problem with a Swift project where I'm creating the buttons dynamically. Problem code:
var trashBarButtonItem: UIBarButtonItem {
return UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: "newButtonClicked")
}
func newButtonClicked(barButtonItem: UIBarButtonItem) {
NSLog("A bar button item on the default toolbar was clicked: \(barButtonItem).")
}
The solution was to add a full colon ':' after the action: e.g.
var trashBarButtonItem: UIBarButtonItem {
return UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: "newButtonClicked:")
}
func newButtonClicked(barButtonItem: UIBarButtonItem) {
NSLog("A bar button item on the default toolbar was clicked: \(barButtonItem).")
}
Full example here: https://developer.apple.com/library/content/samplecode/UICatalog/Listings/Swift_UIKitCatalog_DefaultToolbarViewController_swift.html
The most obvious cause of this (included for completeness) is improperly casting a pointer and calling a method of the wrong class.
NSArray* array = [[NSArray alloc] init];
[(NSDictionary*)array objectForKey: key]; // array is not a dictionary, hence exception
I also had the same issue.
I deleted my uibutton in my storyboard and recreated it .. now everything works fine.
How to debug ‘unrecognized selector send to instance’
In most of the cases Xcode do not take us to the exact line where this issue happen. When app crash you won’t see the line of code that caused this, rather you will be taken to App delegate class, in which the error output may look like:
[UITableViewCellContentView image]: unrecognized selector sent to instance
or
[__NSDictionaryI objectAtIndex:] unrecognized selector sent to instance
or
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[TestApp.MyViewController viewDidLoad:]: unrecognized selector sent to instance 0xDABCDD'
How to find line of code causing this:
Go to breakpoint navigator. Click ‘+’ option. click ‘Exception Breakpoint’. An new widget like following will apear.
Add following condition block:
-[NSObject(NSObject) doesNotRecognizeSelector:]
You can also put breakpoint for all exception.
Now run your code again. this time, breakpoint will trigger when this exception occurs.
WRITTEN BY: Prafulla Singh
Full explanition: https://prafullkumar77.medium.com/how-to-debug-unrecognized-selector-send-to-instance-402473bc23d
I had a similar problem, but for me the solution was slightly different. In my case, I used a Category to extend an existing class (UIImage for some resizing capabilities - see this howto in case you're interested) and forgot to add the *.m file to the build target. Stupid error, but not always obvious when it happens where to look. I thought it's worth sharing...
Another possible solution: Add '-ObjC' to your linker arguments.
Full explanation is here: Objective-C categories in static library
I think the gist is: if the category is defined in a library you are statically linking with, the linker isn't smart enough to link in category methods. The flag above makes the linker link in all objective C classes and categories, not just ones it thinks it needs to based on analyzing your source. (Please feel free to tune or correct that answer. I'm knew to linked languages, so I'm just parroting here).
This happened to my because accidentally erase the " #IBAction func... " inside my UIViewcontroller class code, so in the Storyboard was created the Reference Outlet, but at runtime there was any function to process it.
The solution was to delete the Outlet reference inside the property inspector and then recreate it dragging with command key to the class code.
Hope it helps!
I think you should use the void, instead of the IBAction in return type. because you defined a button programmatically.
I had the same error and I discovered the following:
When you use the code
[self.refreshControl addTarget:self action:#selector(yourRefreshMethod:) forControlEvents:UIControlEventValueChanged];
You may think it's looking for the selector:
- (void)yourRefreshMethod{
(your code here)
}
But it's actually looking for the selector:
- (void)yourRefreshMethod:(id)sender{
(your code here)
}
That selector doesn't exist, so you get the crash.
You can change the selector to receive (id)sender in order to solve the error.
But what if you have other functions that call the refresh function without providing a sender? You need one function that works for both. Easy solution is to add another function:
- (void)yourRefreshMethodWithSender:(id)sender{
[self yourRefreshMethod];
}
And then modify the refresh pulldown code to call that selector instead:
[self.refreshControl addTarget:self action:#selector(yourRefreshMethodWithSender:) forControlEvents:UIControlEventValueChanged];
I'm also doing the Stanford iOS course on an older Mac that can't be upgraded to the newest version of Mac OSX. So I'm still building for iOS 6.1, and this solved the problem for me.
On my case I solved the problem after 2 hours :
The sender (a tabBar item) wasn't having any Referencing Outlet. So it was pointing nowhere.
Juste create a referencing outlet corresponding to your function.
Hope this could help you guys.
I'm currently learning iOS development and going through the "Beginning iOS6 Development" book by aPress. I was getting the same error in Chapter 10:Storyboards.
It took me two days to figure it out but found out I accidentally set the TableView cell's tag to 1 when I shouldn't have. For anyone else doing this book and receive a similar error I hope this helps.
I really hope future errors in my code are easier to find! hahaha. The debug error did nothing to push me in the right direction to figuring it out (or at least I'm too new to understand the debugger, lol).
In my case I was using a UIWebView and I passed a NSString in the second parameter instead of a NSURL. So I suspect that wrong class types passed to a functions can cause this error.
..And now mine
I had the button linked to a method which accessed another button's parameter and that worked great BUT as soon I tried to do something with the button itself, I got a crash. While compiling, no error has been displayed.. Solution?
I failed to link the button to the file's owner. So if anyone here is as stupid as me, try this :)
Yet another slightly different solution/case.
I am using Xamarin and MvvmCross and I was trying to bind the UIButton to a ViewModel. I had the UIButton wired up to an Outlet and a TouchUpInside.
When Binding I only use the Outlet:
set.Bind (somethingOutlet).For ("TouchUpInside").To(vm => vm.Something);
All I had to do was remove the action (TouchUpInside) connection in XCode and that solved it.
P.S.
I guess this is in its base all related to the previous answers and to #Chris Kaminski in particular, but I hope this helps someone...
Cheers.
I had the same issue. The problem for me was that one button had two Action methods. What I did was create a first action method for my button and then deleted it in the view controller, but forgot to disconnect the connection in the main storyboard in the connection inspector. So when I added a second action method, there were now two action methods for one button, which caused the error.
For me, it was a leftover connection created in interfacebuilder bij ctrl-dragging. The name of the broken connection was in the error-log
*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '-[NameOfYourApp.NameOfYourClass nameOfCorruptConnection:]:
unrecognized selector sent to instance 0x7f97a48bb000'
I had an action linked to a button. Pressing the button crashed the app because the Outlet no longer existed in my code.
Searching for the name in the log led me to it in the storyboard. Deleted it, and the crash was gone!
I'm replying to Leonard Challis, since I was also taking the Stanford iOS class C193P, as was user "oli206"
"Terminating app due to uncaught exception 'NSInvalidArgumentException', reason:"
The problem was that I had the "Enter" button on the calculator connected twice,and a friend pointed out that doing an inspection of the button in the Storyboard showed that 2 entries were on the "Touch Up Inside" attributes when I right clicked on the "Enter" button. Erasing one of the two "Touch Up Inside" "Sent Events" solved the problem.
This showed that the problem is triggered (for the C193P video class on the Calculator Walkthrough on Assignment 1) as 2 sent events, one of which was causing the exception.
It can happen when you do not assign the ViewController to the ViewControllerScene in
the InterfaceBuilder. So the ViewController.m is not connected to any scene.
Including my share. I got stuck on this for a while, until I realized I've created a project with ARC(Automatic counting reference) disabled. A quick set to YES on that option solved my issue.
Another really silly cause of this is having the selector defined in the interface(.h) but not in the implementation(.m) (p.e. typo)
Another reason/solution to add to the list. This one is caused by iOS6.0 (and/or bad programming). In older versions the selector would match if the parameter types matched, but in iOS 6.0 I got crashes in previously working code where the name of the parameter wasn't correct.
I was doing something like
[objectName methodName:#"somestring" lat:latValue lng:lngValue];
but in the definition (both .h and .m) I had
(viod) methodName:(NSString *) latitude:(double)latitude longitude:(double)longitude;
This worked fine on iOS5 but not on 6, even the exact same build deployed to different devices.
I don't get why the compiler coudn't tell me this, anyway - problem soled.
This also might happen when you want to set a property from a ControllerA to a public property inside a custom ControllerB class and you haven't set the "Custom Class" inside the identity inspector in storyboards yet.
My problem and solution was different and I thought I should post it here so that future readers can save their head from banging to the wall.
I was allocating different xib to same UIVIewController and even after searching everywhere I couldn't find how to correct it. Then I checked my AppDelegate where I was calling initWithNibName and can see that while copying the code, I changed the xib name, but forgot to change UIViewController class. So if none of the solution works for you, check your initWithNibName method.