How can I debug 'unrecognized selector sent to instance' error
ios, swift, uitableview
Solution
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.
Problem
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.