I got this message when I save data to core data.
NSScanner: nil string argument
I didn't use any NSScanner method. Where did it come from?
This is a bug? What should I do with it?
Thanks help, please.
From experience, I can say that -[NSDecimalNumber initWithString:] or +[NSDecimalNumber decimalNumberWithString:] with a nil string is one thing that causes that log message.
Set a breakpoint on -[NSScanner initWithString:] to start with; if you don't catch it that way, then break on the other ways you might create a scanner, like +scannerWithString: and -[NSConcreteScanner initWithString:]. That's how I flushed my unwanted log statement out.
FWIW, I had this message come out whilst building a core data app.
It was due to me rebuilding and running the app in the simulator, which effectively kills off your running process without going through any of your exit methods.
Depending on when / where you are saving your managed object context, you could be left with an incomplete managed object somewhere, then scanners which would expect to find values would have nothing when the app was relaunched and the half baked objects were returned from the store.
I have the same crash log NSScanner: nil string argument.
This is my sitution
Everything works fine on device.
Crash at dequeueReusableCellWithIdentifier only on simulator
I solved it by
Product->Clean Then rebuild.Every thing works fine for me. I not sure why this happened.
I had met this problem on iOS 9 and iOS 10 BUT iOS 11 work fine,I solved it by removing observer in dealloc where I had used KVO.
Such as:
- (void)dealloc {
[self.collectionView removeObserver:self forKeyPath:#"contentSize"];
}
I got this crash error but not about nil string issue.
My reason is that I use a cell in storyboard as dynamic but set Static Cells in the Attributes inspector. I changed that attribute to Dynamic Prototypes, solved the problem.
Related
I recently updated to Xcode 7 and upgraded my iPhone to iOS 9. I have developed and released an iOS app that had worked perfectly fine on the latest version of iOS 8 and Xcode 6.
Upon trying to go through the process of updated the app for iOS 9 support, I am getting the most ridiculously strange error that has left me baffled.
I have done all the syntax corrections automatically through Xcode, and now my app builds properly. It even runs fine at first.
I have a button that segues to a view controller with a WebView. This view controller loads a link that will display either an image, website, or video from youtube. The content is loaded perfectly fine as always. However, the program will crash and reboot the simulator (and my iPhone) and send me to the lock screen when I click the Back button (I am on a navigation stack).
In Xcode, I get the following messages:
XPC Connection Interrupted.
Terminating since there is no system app.
I have Flurry analytics integrated in my app by the way, not sure if thats an issue.
How can I fix this issue? My searches for XPC connections do not seem to return problems similar to mine. I do not even have a clue what an XPC connection is, so why is this in my app anyway?
EDIT: I have found a workaround for the issue. I cannot really say it is a fix.
The crashing was occurring during the use of the method self.navigationController?.popViewControllerAnimated, when set to true. I happened to set this to false, and the crashing stops (now the transition looks awful).
I do not know why this works, and just adds to my confusion.
The problem lied in the storyboard for me as well. I created a new project and laid out the views and everything seemed to be working fine. I found these couple lines in the storyboard source (right click on storyboard and select view as -> source code) which weren't common between the working version and the broken version:
<keyCommands>
<keyCommand/>
</keyCommands>
I have no idea what those lines are supposed to do, or how they crept into my storyboard file, but they were what was crashing the app so hard that the phone had to restart. I removed those lines from my main project and everything worked again.
This error can be caused by executing a loop repeatedly. In my case it was a 'for' loop in which I reset the counting variable. As soon as I added an NSLog in the loop it was obvious.
I just faced the same problem. I don't know if that will help you, but I also think it's coming from the Storyboard:
In my case, the problem is coming from a UITextView. Whenever I try to change the default text inside it, I have this error. If I let the default text or leave it empty, the app works fine. Making an IBOutlet and changing the text programmatically works as well.
I tried with other UI elements, but only the UITextView seems to have this issue.
I have struggled with exact same error. Through a process of elimination I established that it had nothing to do with the any class but had to do with the storyboard. Luckily I keep regular backup copies and I tried to compare storyboards to establish what I had done - but could find nothing obvious.
The backup copy worked fine and I was able to copy my controller classes (from the faulty copy with the changes) into the backup copy and they worked fine.
I think there is a bug possibly in storyboards.
I have same error message when I place a subview in -layoutSubviews method:
-(void)layoutSubviews
{
[super layoutSubviews];
[self populateByImageViews];
}
It causes infinite cycle of layout process and crashes app. Don't place subviews in this place!
Deleting UITextView from the one of the view in Storybord removes the error in my case.
In valueChanged: method of a UIControl, I had the same problem
so I made the code inside valueChanged: to run in main thread and it solved the problem.
#IBAction func valueChanged(sender: AnyObject) {
dispatch_async(dispatch_get_main_queue(), {
//code
}
}
For me was some missing constraints with a UISearchBar, but the error was only in the simulator.
I only add some constraints and works better
For me it was xcode live issues caused by IB_DESIGNABLE
If you have any IB_DESIGNABLE in source files, the system's live tracker will check for issues in StoryBoard too. It may leads to unnecessary building.
To disable it-
Open Storyboard file. Editor -> Automatically Refresh Views (Uncheck)
If you needs to Disable Live issue tracking
XCode -> Preferences -> General -> Issues -> Uncheck Live Issues
Reference
My issue probably originated with some storyboard issue, but I cleaned the project, restarted Xcode AND restarted the simulator app and that fixed it.
When using QLPreviewController, I am confronted with this problem. Error messages as follows,
XPC connection interrupted
_BSMachError: (os/kern) invalid capability (20)
_BSMachError: (os/kern) invalid name (15)
Since XPC means OS X interprocess communication, so I think this can solve the problem, especial when updating the UI
dispatch_async(dispatch_get_main_queue(), ^{
// do what you want to do.
});
For Swift 4+, user
DispatchQueue.main.async {
//Your Code
}
The application works fine on the simulator but breaks in start up in device as in the figure
I tried some of the solution in SO but It doesnt work out.What may be the reason ?How can i find it? How to resolve it
For clarity
Tried : Changing the view controller the viewcontroller. view did load and all functions are working fine after that when the view tries to appear on the screen the crash appears
UPDATE : Now getting the error logged as
*** -[Not A Type retain]: message sent to deallocated instance 0x208c9610
I had the same issue before. This is not a crash. Please remove all your break points and run it again.
This is a Breakpoint error ..... It normally occurs when you add a breakpoint to an app running in the device. If you add the breakpoints before the app has been built and run it again.... The crash will not occur.
Even I couldn't figure out why this crash should occur in the first place but it does.
OK found out the problem.I am using an external library which does not implement ARC so it has to be flagged.all files except 2 are not flagged as -fno-objc-arc and hence the issue.
I have the following code that works good on iOS 5.1 to replace buttons on the toolbar:
[(UIToolbar*)toolbar setItems:itemsArray];
But compiled application doesn't work on iOS 6. I have compiled sources with xXode 4.5 with iOS 6 support but the error is the same:
2012-09-27 16:31:13.537 Linux[2633:907] -[UIWebFormAccessory setItems:]: unrecognized selector sent to instance 0x1d886ad0
2012-09-27 16:31:13.540 Linux[2633:907] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIWebFormAccessory setItems:]: unrecognized selector sent to instance 0x1d886ad0'
*** First throw call stack:
(0x361032a3 0x3441397f 0x36106e07 0x36105531 0x3605cf68 0x775c5 0x33bbda6f 0x360d85df 0x360d8291 0x360d6f01 0x36049ebd 0x36049d49 0x365862eb 0x37428301 0x7538d 0x75328)
libc++abi.dylib: terminate called throwing an exception
(lldb)
How to fix the issue?
Linked issue: How to replace buttons on a toolbar under UIWebView keyboard on iOS 6?
Thanks a lot for the help!
Even if it is a UIToolbar, which it might not be any longer, you're obviously trying to call a method (or "send a message") that doesn't exist. The solution is to not do that since the method won't just reappear out of nothing once you try hard enough.
It may be the case that there's another way to continue doing what you're trying to do by finding another fitting method on this undocumented type. However, maybe that will also break someday like this just broke. If they don't document something, yes, it means you can still use it (at least up until you send it for review), but it also means that it might break at any time.
A long term solution is to work out a way to bring up your own interface which you can control yourself. Knowing where you want to integrate, I don't suppose it's very easy. I think I saw another question about that here on Stack Overflow a few days ago saying to detect touches, stop editing and take over the UI yourself (although it doesn't really play well with cursor positioning, copy/paste menus and so on).
Either way, you'll have to devise a new solution that's not so brittle.
UIWebFormAccessory is not a UIToolbar on iOS6. If you want to mess with the form accessory toolbar, check out the "findVirginWebKeyboardToolbar" answer to your related question: https://stackoverflow.com/a/12865353/199267
are you sure the toolbar in this specific case is actually a UIToolbar? I would guess it's a casting issue.
I do the following in one of my classes, and it definitely works in iOS6
NSMutableArray *items = [NSMutableArray arrayWithArray: self.topToolbar.items];
[items insertObject:barButtonItem
atIndex:0];
self.topToolbar.items = items;
is there something wrong with core data for xcode 4.3.2
I'm following the Stanford Paul Hegarty class for ios 5.0
doing the core data walkthrough (Video 14 Core data demo)
I downloaded the file here
I ran it in xcode 4.3.2 but the core data doesn't seem to work because the entries in the tableview do not appear.
I tried to run it in another computer with xcode 4.2 and ios 5.0
it's working perfectly
anybody who encountered the same problem? I'm pretty sure that xcode is at fault.
Interesting. I am having the same problems and I am also using XCode 4.3, but just thought it was because of the Flickr license that you need and which I don't have. (In FlickAPIKey.h, there is a #define FlickrAPIKey #"" and you won't download anything if you don't have that key.)
Update: I got myself a Flickr API key (you can just get one from their website) and tried the Photomania App on XCode 4.3: it works like a charm, so it looks like XCode is not your problem here. (Although on occasion I found that I had to stop and restart XCode to get rid of a strange bug or compiler error.) Anyway, maybe it is an idea to delete the data first before you try again: Just delete the App before you run it and the database file will get deleted as well.
Paul Hegarty after his class, has published an update version of his code which have a call to SAVE the CoreData database! This may be the reason why your CoreData informations doesn't persist.
His update note was:
// should probably saveToURL:forSaveOperation:(UIDocumentSaveForOverwriting)completionHandler: here!
// we could decide to rely on UIManagedDocument's autosaving, but explicit saving would be better
// because if we quit the app before autosave happens, then it'll come up blank next time we run
// this is what it would look like (ADDED AFTER LECTURE) ...
[document saveToURL:document.fileURL forSaveOperation:UIDocumentSaveForOverwriting completionHandler:NULL];
So, you have to Add the 'document saveToURL' line in the 'fetchFlickrDataInDocument' function like this:
- (void)fetchFlickrDataIntoDocument:(UIManagedDocument *)document
{
dispatch_queue_t fetchQ = dispatch_queue_create("Flickr fetcher", NULL);
dispatch_async(fetchQ, ^{
NSArray *photos = [FlickrFetcher recentGeoreferencedPhotos];
[document.managedObjectContext performBlock:^{
// perform in the NSMOC's safe thread (main thread)
for (NSDictionary *flickrInfo in photos) {
[Photo photoWithFlickrInfo:flickrInfo inManagedObjectContext:document.managedObjectContext];
// table will automatically update due to NSFetchedResultsController's observing of the NSMOC
}
// should probably saveToURL:forSaveOperation:(UIDocumentSaveForOverwriting)completionHandler: here!
// we could decide to rely on UIManagedDocument's autosaving, but explicit saving would be better
// because if we quit the app before autosave happens, then it'll come up blank next time we run
// this is what it would look like (ADDED AFTER LECTURE) ...
[document saveToURL:document.fileURL forSaveOperation:UIDocumentSaveForOverwriting completionHandler:NULL];
// note that we don't do anything in the completion handler this time
}];
});
}
If someone is still facing the same issue using Objective-C, there is one more thing you need to do after getting API key: change all http:// to https:// within files in FlickrFetcher folder. This worked for me.
I have a crash that is happening deep within UIKit for some reason; an EXC_BAD_ACCESS error is happening something like 8 calls deep into a dismissModalViewController call. I tried enabling NSZombieEnabled for my executable, but the console log prints the same error regardless of whether or not zombies are turned on and i don't know which object is causing the issue. Is there something i'm missing that i need to do to get the console to print the correct information?
Read about using Zombies here.
Run this in gdb. When you get the EXC_BAD_ACCESS look at the stack at that point (use gdb's where command or run the Xcode GUI debugger). If you are still having issues, post the stack in your original question.
Also zombies will only help you if you're dealing with NSObjects. If you're using low level malloc/free routines zombies buy you nothing for those allocations.
One thing I learned last weekend when NSZombieEnabled didn't seem to be working at all - make sure you're not passing in a non-object to some code.
In my case, I was returning an NSString as just "string" instead of #"string". That meant I was overwriting an NSString object with the c-string. When I later tried to write a new value in that object I was getting a BAD_ACCESS. NSZombie's couldn't help b/c it was not an object I was trying to overwrite, but that c-string.
As an aside, treat all warnings as errors in XCode - wish I could make them show up in RED in the IDE GUI - they are easy to miss sometimes.
Sounds like something is over-released in your Modal View Controller. Start by commenting out newish lines until it stops breaking.