I'm having an exception in my didSelectRowAtIndexPath method and i'm not quite sure why. I'm showing the user a list of possibilities they can select from, the UITableView is populated based on values stored in Core Data. The currently selected item has a Checkmark indicator. My method is below:
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
tableView.deselectRowAtIndexPath(indexPath, animated: true)
let value = self.fetchedResultsController.objectAtIndexPath(indexPath) as CoreDataObject
currentSelected = value.id as Int
self.tableView.reloadData()
}
In development mode it's fine, but in production and testflight it crashes in this method. The crash log is below:
Crashed Thread 0 :
0 CoreFoundation 0x25f41a7d _CFRetain + 165
1 UIKit 0x29619d67 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 919
2 UIKit 0x296cb9df -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 195
3 UIKit 0x2957da25 _applyBlockToCFArrayCopiedToStack + 309
4 UIKit 0x294f982b _afterCACommitHandler + 459
5 CoreFoundation 0x26007d95 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 21
6 CoreFoundation 0x26005453 __CFRunLoopDoObservers + 279
7 CoreFoundation 0x2600585b __CFRunLoopRun + 915
8 CoreFoundation 0x25f533c1 CFRunLoopRunSpecific + 477
9 CoreFoundation 0x25f531d3 CFRunLoopRunInMode + 107
10 GraphicsServices 0x2d3510a9 GSEventRunModal + 137
11 UIKit 0x29562fa1 UIApplicationMain + 1441
Is there anything i'm missing here? Why is this method crashing? I'm simply storing the currently selected ID and then reloading data so that it can show a checkmark after the reload. Is there something i'm missing here? It should be as simple as just getting the new id and then reloading the data.
The CoreDataObject that i'm using is from Objective-C and the id field is an NSNumber.
I tried other solutions below:
Crash when calling selectRowAtIndexPath:animated:scrollPosition:
iphone app crash at -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:]
iOS - didSelectRowAtIndexPath causes crash in app
In case anybody else has this issue. currentSelected was a global variable declared as Int and the value object has an id field thats `NSNumber. I changed it to the below and it works:
self.currentSelected = value.id.integerValue
Related
I'm seeing an unexplained crash on my iOS app built with SwiftUI. It only affects some users, and I can't manage to reproduce locally.
Here is the stack trace:
Fatal Exception: NSInvalidArgumentException
<_TtGC7SwiftUI41StyleContextSplitViewNavigationControllerVS_19SidebarStyleContext_: 0x110859800>
is pushing the same view controller instance(<_TtGC7SwiftUI41StyleContextSplitViewNavigationControllerVS_14NoStyleContext_: 0x11088a400>)
more than once which is not supported and is most likely an error in the application : `com.myapp`
Fatal Exception: NSInvalidArgumentException
0 CoreFoundation 0x1893a186c __exceptionPreprocess
1 libobjc.A.dylib 0x19e3bcc50 objc_exception_throw
2 UIKitCore 0x18b575514 -[UINavigationController pushViewController:transition:forceImmediate:]
3 UIKitCore 0x18b5751f4 -[UINavigationController pushViewController:animated:]
4 UIKitCore 0x18b6047c8 __45-[UISplitViewControllerPanelImpl showColumn:]_block_invoke
5 UIKitCore 0x18b57eda8 -[UINavigationController _executeSplitViewControllerActions:]
6 UIKitCore 0x18b6045bc -[UISplitViewControllerPanelImpl showColumn:]
7 UIKitCore 0x18b5e4c54 -[UISplitViewController showColumn:]
8 SwiftUI 0x1903784f4 closure #1 in closure #1 in NavigationBridge_PhoneTV.push(_:onto:animated:)
9 SwiftUI 0x19042728c thunk for #escaping #callee_guaranteed () -> ()
10 UIKitCore 0x18c23f544 -[_UIAfterCACommitBlock run]
11 UIKitCore 0x18bd6700c _runAfterCACommitDeferredBlocks
12 UIKitCore 0x18bd559a0 _cleanUpAfterCAFlushAndRunDeferredBlocks
13 UIKitCore 0x18bd89bb4 _afterCACommitHandler
14 CoreFoundation 0x18931c358 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__
15 CoreFoundation 0x1893165c4 __CFRunLoopDoObservers
16 CoreFoundation 0x189316b74 __CFRunLoopRun
17 CoreFoundation 0x18931621c CFRunLoopRunSpecific
18 GraphicsServices 0x1a0ee2784 GSEventRunModal
19 UIKitCore 0x18bd56ee8 -[UIApplication _run]
20 UIKitCore 0x18bd5c75c UIApplicationMain
21 MYAPP 0x100dbecc0 main + 7 (PushupsMode.swift:7)
22 libdyld.dylib 0x188fd66b0 start
Looking at PushupsMode.swift:7 it seems completely unrelated:
import Foundation
extension WorkoutModel {
mutating func startPushups() {
var pushupsCount = 10 + p.intensityOptionPicked * 10
if(round > 6 || round < 3) { // <<--- this is the line crashing
pushupsCount = Int(pushupsCount / 2)
}
// More code after that point
}
}
The round variable is defined in another file, but there's nothing really significant around it:
import Foundation
import SwiftUI
struct WorkoutModel: Identifiable {
// bunch of stuff before
var round: Int = -1
// bunch of stuff after
}
Obviously looking at the error message, it seems like something is getting pushed twice... however since I'm using SwiftUI I'm not entirely sure how I could have even done that.
Any pointers would be appreciated!
Your problem may be that you are defining pushupsCount as an Int( on PushupsMode.swift:8 which is causing the exception on :7 from :8 failing pre-execution. Try defining it as pushupsCount = Int pushupsCount / 2 .
Using pushViewController:transition:forceImmediate is not a good idea because pushViewController:animated will be calling on this undocumented method. Rather than changing transition this way you can use other documented methods for changing animation. This thread might be helpful for you. You will also need to add guard in pushViewController:animated and will also need to set transition.duration. Calling pushViewController again and again is perhaps causing crash of app.
This problem is caused when you place your navigationLink inside of a List with observed data.
How to fix :
Remove NavigationLink from inside of the list and place it outside.
i have a strange reaction with my app.
My app is working fine in almost 10 different devices and also has passed the tests and it's online. But one friend that has iPhone 5s with iOS 9.1 has an issue. When he tries to enter to a table view, which i append items to it with an API call with alamofire and swiftyjson.. the app crashes. From crashlytics i get this strange error
Crashed: com.apple.main-thread
0 Events Near Me 0x1000a532c specialized listMapViewController.tableView(UITableView, cellForRowAtIndexPath : NSIndexPath) -> UITableViewCell (listMapViewController.swift:196)
1 Events Near Me 0x1000a3c94 #objc listMapViewController.tableView(UITableView, cellForRowAtIndexPath : NSIndexPath) -> UITableViewCell (listMapViewController.swift)
2 UIKit 0x18a37220c -[UITableView _createPreparedCellForGlobalRow:withIndexPath:willDisplay:] + 688
3 UIKit 0x18a372364 -[UITableView _createPreparedCellForGlobalRow:willDisplay:] + 80
4 UIKit 0x18a3617b8 -[UITableView _updateVisibleCellsNow:isRecursive:] + 2440
5 UIKit 0x18a376f0c -[UITableView _performWithCachedTraitCollection:] + 104
6 UIKit 0x18a10f22c -[UITableView layoutSubviews] + 176
7 UIKit 0x18a01f7ac -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 644
8 QuartzCore 0x18981eb58 -[CALayer layoutSublayers] + 148
9 QuartzCore 0x189819764 CA::Layer::layout_if_needed(CA::Transaction*) + 292
10 QuartzCore 0x189819624 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 32
11 QuartzCore 0x189818cc0 CA::Context::commit_transaction(CA::Transaction*) + 252
12 QuartzCore 0x189818a08 CA::Transaction::commit() + 512
13 QuartzCore 0x1898120f8 CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 80
14 CoreFoundation 0x184a47bd0 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 32
15 CoreFoundation 0x184a45974 __CFRunLoopDoObservers + 372
16 CoreFoundation 0x184a45da4 __CFRunLoopRun + 928
17 CoreFoundation 0x184974ca0 CFRunLoopRunSpecific + 384
18 GraphicsServices 0x18fbb0088 GSEventRunModal + 180
19 UIKit 0x18a08cffc UIApplicationMain + 204
20 Events Near Me 0x100095eec main (AppDelegate.swift:15)
21 libdyld.dylib 0x199da28b8 start + 4
And in the line 196 this is the code
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! locationEventsTableViewCell
var dict = arrRes[indexPath.row]
cell.eventTitle.text = dict["eventName"] as? String //here is the issue
So to explain you a bit, with this app you get some events near you depending on your location. I have a protection if there are no events there is a message. But we leave a couple of blocks away and i can get events, among with the cell.eventTitle... but my friend's iPhone crashes through it.
Any idea?
P.S. i'm now downloading iOS 9.1 to my simulator. Another friend with iPhone 5 doesnt have that issue.
As you say that other iphones doesn't have this problem I assumed that your friend's iphone maybe is overloaded from apps or anything else and it doesn't take the json variables in time!
So I suggest first to use if statements to avoid errors like this:
if dict["eventName"] as? String != nil {
cell.eventTitle.text = dict["eventName"] as? String
}
And if you want in your next update maybe you could use completions to reload your tableView data.
Hope it helps.
I have received the below exception backtrace from Apple for an app I had submitted to the app store. I have symbolicated the log but my app's entry has not symbolicated. Any idea what I can do to achieve that? Please see Entry # 14 below which provides more detail. Any help would be much appreciated
Last Exception Backtrace:
0 CoreFoundation 0x1810cadb0 __exceptionPreprocess + 124
1 libobjc.A.dylib 0x18072ff80 objc_exception_throw + 56
2 UIKit 0x186b6d268 -[UIPopoverPresentationController presentationTransitionWillBegin] + 2884
3 UIKit 0x186581fb0 __71-[UIPresentationController _initViewHierarchyForPresentationSuperview:]_block_invoke + 1640
4 UIKit 0x1865800c8 __56-[UIPresentationController runTransitionForCurrentState]_block_invoke + 332
5 UIKit 0x1864d30c8 _runAfterCACommitDeferredBlocks + 292
6 UIKit 0x1864e0a80 _cleanUpAfterCAFlushAndRunDeferredBlocks + 92
7 UIKit 0x1862125a4 _afterCACommitHandler + 96
8 CoreFoundation 0x181080728 _CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 32
9 CoreFoundation 0x18107e4cc __CFRunLoopDoObservers + 372
10 CoreFoundation 0x18107e8fc __CFRunLoopRun + 928
11 CoreFoundation 0x180fa8c50 CFRunLoopRunSpecific + 384
12 GraphicsServices 0x182890088 GSEventRunModal + 180
13 UIKit 0x18628a088 UIApplicationMain + 204
14 MyApp 0x1000fb144 0x1000e4000 + 94532
15 libdyld.dylib 0x180b468b8 start + 4
Finally solved the problem. I was invoking UIAlertController in my code to present an action sheet with various options. To cater to devices that don't have a camera, I had added a conditional statement to directly present an ImagePicker instead of an action sheet.
iPAD testing was carried out only on the simulator which doesn't have a camera, thus directly invoking the ImagePicker. When he Conditional statement was removed, it tried presenting the Action Sheet through a PopoverPresentationController and crashed - as is evident in statement 2 of the Exception Backtrace.
I subsequently added the following code to fix the oversight:
if let popOver = optionMenu.popoverPresentationController {
popOver.sourceRect = sender.bounds
popOver.sourceView = sender
}
I have this code:
override func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
var array: AnyObject = []
for obj in Category.allObjects() {
if var add = obj as? Category {
array.addObject(add.name)
println(add.name)
}
}
return String(array[section] as String)
}
Im using a Realm database and I am trying to get one of the columns of the database to print in the section headers. Im also using a the same process for all the other required UITableView methods eg/ numberOfSectionsInTable etc etc. The code is giving me this error:
2014-10-26 20:47:33.479 Project[14631:937721] -[__NSArrayI addObject:]: unrecognized selector sent to instance 0x7fdaf270ddb0
2014-10-26 20:47:33.481 Project[14631:937721] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI addObject:]: unrecognized selector sent to instance 0x7fdaf270ddb0'
*** First throw call stack:
(
0 CoreFoundation 0x0000000109960f35 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x00000001095f9bb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010996804d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x00000001098c027c ___forwarding___ + 988
4 CoreFoundation 0x00000001098bfe18 _CF_forwarding_prep_0 + 120
5 BuildersUtility 0x0000000108d7f720 _TFC15BuildersUtility29ProductsDetailsViewController27numberOfSectionsInTableViewfS0_FCSo11UITableViewSi + 1408
6 BuildersUtility 0x0000000108d7f8ca _TToFC15BuildersUtility29ProductsDetailsViewController27numberOfSectionsInTableViewfS0_FCSo11UITableViewSi + 58
7 UIKit 0x000000010a478a7e -[UITableViewRowData _updateNumSections] + 84
8 UIKit 0x000000010a479474 -[UITableViewRowData invalidateAllSections] + 69
9 UIKit 0x000000010a2cdb03 -[UITableView _updateRowData] + 214
10 UIKit 0x000000010a2e300f -[UITableView numberOfSections] + 27
11 UIKit 0x000000010a4e0645 -[UITableViewController viewWillAppear:] + 97
12 UIKit 0x000000010a327821 -[UIViewController _setViewAppearState:isAnimating:] + 487
13 UIKit 0x000000010a352960 -[UINavigationController _startTransition:fromViewController:toViewController:] + 776
14 UIKit 0x000000010a353487 -[UINavigationController _startDeferredTransitionIfNeeded:] + 523
15 UIKit 0x000000010a353f47 -[UINavigationController __viewWillLayoutSubviews] + 43
16 UIKit 0x000000010a499509 -[UILayoutContainerView layoutSubviews] + 202
17 UIKit 0x000000010a277973 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 521
18 QuartzCore 0x000000010a089de8 -[CALayer layoutSublayers] + 150
19 QuartzCore 0x000000010a07ea0e _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
20 QuartzCore 0x000000010a07e87e _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 24
21 QuartzCore 0x0000000109fec63e _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 242
22 QuartzCore 0x0000000109fed74a _ZN2CA11Transaction6commitEv + 390
23 QuartzCore 0x0000000109feddb5 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 89
24 CoreFoundation 0x0000000109895dc7 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
25 CoreFoundation 0x0000000109895d20 __CFRunLoopDoObservers + 368
26 CoreFoundation 0x000000010988bb53 __CFRunLoopRun + 1123
27 CoreFoundation 0x000000010988b486 CFRunLoopRunSpecific + 470
28 GraphicsServices 0x000000010dec79f0 GSEventRunModal + 161
29 UIKit 0x000000010a1fe420 UIApplicationMain + 1282
30 BuildersUtility 0x0000000108d9589e top_level_code + 78
31 BuildersUtility 0x0000000108d958da main + 42
32 libdyld.dylib 0x000000010baaf145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
BTW if you have a better way for me to extract the code from the database for a project like this please chirp in! :)
Thanks in Advance
allObjects will return you an instance of RLMResults, which is one of the two list types in Realms, the other being RLMArray. They are both made to be similar to NSArrays or swift arrays, and implement a protocol called RLMCollection. Among other things, that means you can access its elements with normal [i] notation. So you can simply write
return Category.allObjects()[section].name
although you might want to do some checking before you return. Also, it is generally not advisable to repeat the allObjects() query more than you need to, so you could cache in a lazy instance variable or similar. In this case there probably aren't that many categories/section headers, so it shouldn't be an issue.
More importantly, keep in mind that although the RLMResults list you get back is ordered in the sense that it is an ordered list, there is no inherent order among the Category instances in the Realm, so the next time you do Category.allObjects() you are not really guaranteed to receive the objects in the same order. So what you should do is really to create an RLMArray of Category objects and make that a property of another object. Then the order will be preserved.
It is because AnyObject does not support the method addObject
I think what you have in mind is that you want the variable array to be an array of type AnyObject.
You should declare it this way:
var array:[AnyObject] = []
And then when you want to add anything to the array, do this:
array.append(add.name)
In addition to what #AnthonyKong is pointing out, it is a bit unclear from the above code why you would want an array of AnyObject in the first place.
var array = [AnyObject]()
It seems what you actually want is an array of String?
var array = [String]()
then your return statement is simplified down to:
return array[section]
When feeling up to it you might also look into filter to rip out some of that almost-boiler-plate-logic in your code.
I had a similar problem but with an NSMutableArray. Thanks to #Gusutafu's comment above that setting an array to #[] converts it to an NSArray.
My incorrect code (selectedTags is an NSMutableArray):
selectedTags = ([theInputParameters valueForKey:kAcronymTagsSelectedTags] != nil)
? [theInputParameters valueForKey:kAcronymTagsSelectedTags]
: #[];
This gave the error -[__NSArrayI addObject:]: unrecognized selector sent to instance when I tried to add an object.
My corrected code
selectedTags = ([theInputParameters valueForKey:kAcronymTagsSelectedTags] != nil)
? [theInputParameters valueForKey:kAcronymTagsSelectedTags]
: [NSMutableArray arrayWithArray:#[]];
I am creating a custom table cell view for my table view. After I connect an image view of custom cell (in storyboard) to my code in swift, I get the following error.
[UITableViewCellContentView image]: unrecognized selector sent to instance 0x7fb4fad7fd20'
*** First throw call stack:
(
0 CoreFoundation 0x000000010ccbb3f5 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x000000010e7e9bb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010ccc250d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x000000010cc1a7fc ___forwarding___ + 988
4 CoreFoundation 0x000000010cc1a398 _CF_forwarding_prep_0 + 120
5 UIKit 0x000000010d7d8881 -[UITableViewCell _marginWidth] + 151
6 UIKit 0x000000010d7ca23d -[UITableViewCell _separatorFrame] + 70
7 UIKit 0x000000010d7ca6fa -[UITableViewCell _updateSeparatorContent] + 360
8 UIKit 0x000000010d7d4e85 -[UITableViewCell _setSectionLocation:animated:forceBackgroundSetup:] + 1174
9 UIKit 0x000000010d634ea8 __53-[UITableView _configureCellForDisplay:forIndexPath:]_block_invoke + 1822
10 UIKit 0x000000010d5b5eae +[UIView(Animation) performWithoutAnimation:] + 65
11 UIKit 0x000000010d63477b -[UITableView _configureCellForDisplay:forIndexPath:] + 312
12 UIKit 0x000000010d63bcec -[UITableView _createPreparedCellForGlobalRow:withIndexPath:willDisplay:] + 533
13 UIKit 0x000000010d61b7f1 -[UITableView _updateVisibleCellsNow:isRecursive:] + 2846
14 UIKit 0x000000010d63165c -[UITableView layoutSubviews] + 213
15 UIKit 0x000000010d5be199 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 521
16 QuartzCore 0x00000001114b6f98 -[CALayer layoutSublayers] + 150
17 QuartzCore 0x00000001114abbbe _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
18 QuartzCore 0x00000001114aba2e _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 24
19 QuartzCore 0x0000000111419ade _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 242
20 QuartzCore 0x000000011141abea _ZN2CA11Transaction6commitEv + 390
21 QuartzCore 0x000000011141b255 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 89
22 CoreFoundation 0x000000010cbf0347 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
23 CoreFoundation 0x000000010cbf02a0 __CFRunLoopDoObservers + 368
24 CoreFoundation 0x000000010cbe60d3 __CFRunLoopRun + 1123
25 CoreFoundation 0x000000010cbe5a06 CFRunLoopRunSpecific + 470
26 GraphicsServices 0x0000000110daa9f0 GSEventRunModal + 161
27 UIKit 0x000000010d545550 UIApplicationMain + 1282
28 TestWork 0x000000010caa432e top_level_code + 78
29 TestWork 0x000000010caa436a main + 42
30 libdyld.dylib 0x000000010efc3145 start + 1
31 ??? 0x0000000000000001 0x0 + 1
)
Can you please tell me how to resolve this error?
Thank you.
I add an exception breakpoint in my project.
This is the line where it breaks.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = self.tableView.dequeueReusableCellWithIdentifier(kCellIdentifier) as ItemTableViewCell <---------------
But I don't use 'image' in my code.
Try setting a symbolic breakpoint on -[NSObject(NSObject) doesNotRecognizeSelector:]. Just click [+] in the bottom left corner of the Breakpoint Navigator to add a breakpoint. Then click 'Add Symbolic Breakpoint'. Reproducing your crash now should give you a better idea where in your code the issue occurs.
You can easily track such crashes using Exception Breakpoints.
Open the Breakpoint Navigator and add the
Once you add the Exception Breakpoint, option will be open to choose the Exception.
Select Objective-C.
Run the code and crash the application, breakpoint will stop you to the point where the code is crashing.
The critical first step is to analyze the error message:
[UITableViewCellContentView image]: unrecognized selector sent to instance
This tells you that the "message" image was "sent" to an object of class UITableViewCellContentView. (In other words, an attempt was made to call the method image on an object of class UITableViewCellContentView.)
The first thing to ask is "Does this make any sense at all?" It may be that the named class has an Image method, but not an image method, and so the wrong method name was used on the call. Or it may be that the named method is someMethod:someParm:, but the class implements someMethod:someParm:anotherParm:, meaning that a parameter was omitted on the call.
Most often, though, the named class does not have any method even vaguely resembling the named method, meaning that somehow a pointer to the wrong object was used in the failing call.
For instance, one might do:
NSArray* myArray = [myDictionary objectForKey:#"values"];
NSString* myString = [myArray objectAtIndex:5];
And get an error along the lines of:
[__NSDictionaryI objectAtIndex:] unrecognized selector sent to instance
because the object retrieved from myDictionary was, in fact, an NSDictionary, not the NSArray that was expected.
Most confusing, unfortunately, is when this sort of error occurs deep in UI system code rather than in your own code. This can happen when you somehow passed the wrong object to a system interface, or perhaps configured the wrong class in Interface Builder or wherever.
Another possible reason is that the original object was destroyed and then another object was allocated at the same memory address. Then your code sends the message, thinking it still has a pointer to the old object, and Objective-C throws an exception because the new object doesn't understand that message.
To diagnose this problem, run the Profiler with 'Zombies' detection.
Swift 5.0
You can use Introspection to find out whether object responds to a particular selector or not..
let canWork = yourObject.respondsToSelector(Selector("image")) // true
Only if it is true that code will work.. otherwise it will crash for sure
In these scenarios I've found it helpful to look at two things
The call-stack
The local variables (and their types) at each stack frame
When I've had this error, it's usually because I sent a message to an instance of Type A, when I was expecting Type B.
In this specific scenario, you may not be satisfying a requirement of a parent class (given your instance of ItemTableViewCell most likely inherits).
Can you maybe show us the code for your ItemTableViewCell class?
You can use the following code to declare the variable:
let noteListTableViewCellobject = "NoteListTableViewCell";` `// Note listTablecell create custom cell`
func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
var cell:NoteListTableViewCell? = tableView.dequeueReusableCellWithIdentifier(noteListTableViewCellobject) as? NoteListTableViewCell
if (cell == nil) {
let nib:Array = NSBundle.mainBundle().loadNibNamed("NoteListTableViewCell", owner: self, options: nil)
cell = nib[0] as? NoteListTableViewCell
}
}
I had the same problem, and this worked for me:
Override the isEqual in your SKScene:
- (BOOL)isEqual:(id)other {
if (![other isMemberOfClass:[SKScene class]]) {
return false;
}
return [super isEqual:other];
}
You have to pass indexPath to declare object of tableview cell.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
return cell
}