caught non-fatal NSInvalidArgumentExecption in -[NSScrollView reloadData] - swift

Question

I have built a document based app in swift and then I added a NSCollectionView to it with an add button next to it. The button would call a NSOpenPanel and then the icon of the item chosen should appear in the collection view. However, when I click the 'open' button in the NSOpenPanel, the following were printed to the console:
2017-01-30 19:36:54.205343 CookRecipes[5004:203650] -[NSScrollView reloadData]: unrecognized selector sent to instance 0x6180001c1770
2017-01-30 19:36:54.224746 CookRecipes[5004:203650] -[NSVBSavePanel didEndPanelWithReturnCode:] caught non-fatal NSInvalidArgumentException '-[NSScrollView reloadData]: unrecognized selector sent to instance 0x6180001c1770' with backtrace (
0 CoreFoundation 0x00007fff9e2010db __exceptionPreprocess + 171
1 libobjc.A.dylib 0x00007fffb2e92a2a objc_exception_throw + 48
2 CoreFoundation 0x00007fff9e281cd4 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
3 CoreFoundation 0x00007fff9e1742a3 ___forwarding___ + 1059
4 CoreFoundation 0x00007fff9e173df8 _CF_forwarding_prep_0 + 120
5 CookRecipes 0x0000000100004239 _TFFC11CookRecipes8Document7addFileFT_T_U_FSiT_ + 457
6 CookRecipes 0x00000001000047ef _TTRXFo_dSi__XFdCb_dSi__ + 47
7 AppKit 0x00007fff9c0665e4 -[NSVBSavePanel didEndPanelWithReturnCode:] + 68
8 AppKit 0x00007fff9c6ba09d -[NSVBSavePanel completeModeless:] + 74
9 AppKit 0x00007fff9befa721 -[NSVBSavePanel observeValueForKeyPath:ofObject:change:context:] + 597
10 Foundation 0x00007fff9fbcb71d NSKeyValueNotifyObserver + 350
11 Foundation 0x00007fff9fbcafb4 NSKeyValueDidChange + 486
12 Foundation 0x00007fff9fb99e96 -[NSObject(NSKeyValueObserverNotification) didChangeValueForKey:] + 118
13 ViewBridge 0x00007fffb184c066 __41-[NSViewBridge setObject:forKey:withKVO:]_block_invoke + 447
14 ViewBridge 0x00007fffb18d052b withHintInProgress + 487
15 ViewBridge 0x00007fffb184be83 -[NSViewBridge setObject:forKey:withKVO:] + 1014
16 ViewBridge 0x00007fffb184a95a -[NSViewBridge nonLocalChangeInProgress:block:] + 390
17 ViewBridge 0x00007fffb18aa260 -[NSRemoteViewMarshal exceptionSafeSetRemoteObject:forKey:withReply:] + 256
18 ViewBridge 0x00007fffb18aa3e8 -[NSRemoteViewMarshal setRemoteObject:forKey:withReply:] + 56
19 CoreFoundation 0x00007fff9e1756dc __invoking___ + 140
20 CoreFoundation 0x00007fff9e175561 -[NSInvocation invoke] + 289
21 ViewBridge 0x00007fffb18d052b withHintInProgress + 487
22 ViewBridge 0x00007fffb18d025a __deferNSXPCInvocationOntoMainThread_block_invoke_2 + 233
23 ViewBridge 0x00007fffb1851df2 +[NSViewServiceApplication withHostPID:invoke:] + 46
24 ViewBridge 0x00007fffb18d011d __deferNSXPCInvocationOntoMainThread_block_invoke + 179
25 ViewBridge 0x00007fffb18cfd0a __deferBlockOntoMainThread_block_invoke_2 + 544
26 CoreFoundation 0x00007fff9e19771c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
27 CoreFoundation 0x00007fff9e1789d4 __CFRunLoopDoBlocks + 356
28 CoreFoundation 0x00007fff9e178516 __CFRunLoopRun + 1894
29 CoreFoundation 0x00007fff9e177b54 CFRunLoopRunSpecific + 420
30 HIToolbox 0x00007fff9d702a5c RunCurrentEventLoopInMode + 240
31 HIToolbox 0x00007fff9d702891 ReceiveNextEventCommon + 432
32 HIToolbox 0x00007fff9d7026c6 _BlockUntilNextEventMatchingListInModeWithFilter + 71
33 AppKit 0x00007fff9bca85b4 _DPSNextEvent + 1120
34 AppKit 0x00007fff9c422d6b -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 2789
35 AppKit 0x00007fff9bc9cf35 -[NSApplication run] + 926
36 AppKit 0x00007fff9bc67850 NSApplicationMain + 1237
37 CookRecipes 0x000000010000c344 main + 84
38 libdyld.dylib 0x00007fffb3774255 start + 1
39 ??? 0x0000000000000003 0x0 + 3
)
2017-01-30 19:36:54.239473 CookRecipes[5004:203650] -[NSVBSavePanel observeValueForKeyPath:ofObject:change:context:] caught non-fatal NSInvalidArgumentException '-[NSScrollView reloadData]: unrecognized selector sent to instance 0x6180001c1770' with backtrace (
0 CoreFoundation 0x00007fff9e2010db __exceptionPreprocess + 171
1 libobjc.A.dylib 0x00007fffb2e92a2a objc_exception_throw + 48
2 CoreFoundation 0x00007fff9e281cd4 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
3 CoreFoundation 0x00007fff9e1742a3 ___forwarding___ + 1059
4 CoreFoundation 0x00007fff9e173df8 _CF_forwarding_prep_0 + 120
5 CookRecipes 0x0000000100004239 _TFFC11CookRecipes8Document7addFileFT_T_U_FSiT_ + 457
6 CookRecipes 0x00000001000047ef _TTRXFo_dSi__XFdCb_dSi__ + 47
7 AppKit 0x00007fff9c0665e4 -[NSVBSavePanel didEndPanelWithReturnCode:] + 68
8 AppKit 0x00007fff9c6ba09d -[NSVBSavePanel completeModeless:] + 74
9 AppKit 0x00007fff9befa721 -[NSVBSavePanel observeValueForKeyPath:ofObject:change:context:] + 597
10 Foundation 0x00007fff9fbcb71d NSKeyValueNotifyObserver + 350
11 Foundation 0x00007fff9fbcafb4 NSKeyValueDidChange + 486
12 Foundation 0x00007fff9fb99e96 -[NSObject(NSKeyValueObserverNotification) didChangeValueForKey:] + 118
13 ViewBridge 0x00007fffb184c066 __41-[NSViewBridge setObject:forKey:withKVO:]_block_invoke + 447
14 ViewBridge 0x00007fffb18d052b withHintInProgress + 487
15 ViewBridge 0x00007fffb184be83 -[NSViewBridge setObject:forKey:withKVO:] + 1014
16 ViewBridge 0x00007fffb184a95a -[NSViewBridge nonLocalChangeInProgress:block:] + 390
17 ViewBridge 0x00007fffb18aa260 -[NSRemoteViewMarshal exceptionSafeSetRemoteObject:forKey:withReply:] + 256
18 ViewBridge 0x00007fffb18aa3e8 -[NSRemoteViewMarshal setRemoteObject:forKey:withReply:] + 56
19 CoreFoundation 0x00007fff9e1756dc __invoking___ + 140
20 CoreFoundation 0x00007fff9e175561 -[NSInvocation invoke] + 289
21 ViewBridge 0x00007fffb18d052b withHintInProgress + 487
22 ViewBridge 0x00007fffb18d025a __deferNSXPCInvocationOntoMainThread_block_invoke_2 + 233
23 ViewBridge 0x00007fffb1851df2 +[NSViewServiceApplication withHostPID:invoke:] + 46
24 ViewBridge 0x00007fffb18d011d __deferNSXPCInvocationOntoMainThread_block_invoke + 179
25 ViewBridge 0x00007fffb18cfd0a __deferBlockOntoMainThread_block_invoke_2 + 544
26 CoreFoundation 0x00007fff9e19771c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
27 CoreFoundation 0x00007fff9e1789d4 __CFRunLoopDoBlocks + 356
28 CoreFoundation 0x00007fff9e178516 __CFRunLoopRun + 1894
29 CoreFoundation 0x00007fff9e177b54 CFRunLoopRunSpecific + 420
30 HIToolbox 0x00007fff9d702a5c RunCurrentEventLoopInMode + 240
31 HIToolbox 0x00007fff9d702891 ReceiveNextEventCommon + 432
32 HIToolbox 0x00007fff9d7026c6 _BlockUntilNextEventMatchingListInModeWithFilter + 71
33 AppKit 0x00007fff9bca85b4 _DPSNextEvent + 1120
34 AppKit 0x00007fff9c422d6b -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 2789
35 AppKit 0x00007fff9bc9cf35 -[NSApplication run] + 926
36 AppKit 0x00007fff9bc67850 NSApplicationMain + 1237
37 CookRecipes 0x000000010000c344 main + 84
38 libdyld.dylib 0x00007fffb3774255 start + 1
39 ??? 0x0000000000000003 0x0 + 3
)
I think that the code that the problem is in should be in this segment:
extension Document : AddAttachmentDelegate {
internal func addFile() {
let panel = NSOpenPanel()
panel.allowsMultipleSelection = false
panel.canChooseDirectories = false
panel.canChooseFiles = true
panel.begin { (result) -> Void in
if result == NSModalResponseOK, let resultURL = panel.urls.first {
do {
try self.addAttachmentAtURL(url: resultURL)
self.attachmentsList?.reloadData()
} catch let error as NSError {
if let window = self.windowForSheet {
NSApp.presentError(error, modalFor: window, delegate: nil, didPresent: nil, contextInfo: nil)
} else {
NSApp.presentError(error)
}
}
}
}
}
}
I have no idea what is going on. Hope you can help.
EDIT: attachmentsList is connected by the following:
#IBOutlet weak var attachmentsList: NSCollectionView!