Fatal Exception: NSInternalInconsistencyException

[allenwang-code]

Is this something wrong with the library? Thanks : )

Fatal Exception: NSInternalInconsistencyException UICollectionView received layout attributes for a cell with an index path that does not exist: <NSIndexPath: 0x1cc220c60> {length = 2, path = 0 - 3}

Fatal Exception: NSInternalInconsistencyException 0 CoreFoundation 0x184916d8c __exceptionPreprocess 1 libobjc.A.dylib 0x183ad05ec objc_exception_throw 2 CoreFoundation 0x184916bf8 +[NSException raise:format:] 3 Foundation 0x185306fa0 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] 4 UIKit 0x18e7fb440 __45-[UICollectionViewData validateLayoutInRect:]_block_invoke 5 UIKit 0x18e65c9e8 -[UICollectionViewData validateLayoutInRect:] 6 UIKit 0x18e65b6b4 -[UICollectionView layoutSubviews] 7 UIKit 0x18e52a6f4 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] 8 QuartzCore 0x188a9fe54 -[CALayer layoutSublayers] 9 QuartzCore 0x188aa3fe4 CA::Layer::layout_if_needed(CA::Transaction*) 10 QuartzCore 0x188a106c8 CA::Context::commit_transaction(CA::Transaction*) 11 QuartzCore 0x188a381b0 CA::Transaction::commit() 12 QuartzCore 0x188a39030 CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) 13 CoreFoundation 0x1848be910 CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION 14 CoreFoundation 0x1848bc238 __CFRunLoopDoObservers 15 CoreFoundation 0x1848bc884 __CFRunLoopRun 16 CoreFoundation 0x1847dcda8 CFRunLoopRunSpecific 17 GraphicsServices 0x1867c2020 GSEventRunModal 18 UIKit 0x18e7fc758 UIApplicationMain 19 Baby2Body 0x10202cda4 main (DataManager.swift:21) 20 libdyld.dylib 0x18426dfc0 start