UICollectionView Assertion failure

objective-c ios6 uicollectionview
jajo87 picture jajo87 · Sep 27, 2012 · Viewed 36.8k times · Source

I m getting this error on performing insertItemsAtIndexPaths in UICollectionView

Assertion failure in: 

-[UICollectionViewData indexPathForItemAtGlobalIndex:], 
/SourceCache/UIKit/UIKit-2372/UICollectionViewData.m:442
2012-09-26 18:12:34.432  
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', 
reason: 'request for index path for global index 805306367 
when there are only 1 items in the collection view'

I have checked and my datasource contains only one element. Any insights on why this could happen? If more information is needed I can definitely provide that.

Answer

Jay Slupesky picture Jay Slupesky · Oct 19, 2012

I ran into this very same problem when inserting the first cell into a collection view. I fixed the problem by changing my code so that I call the UICollectionView

- (void)reloadData

method when inserting the first cell, but 

- (void)insertItemsAtIndexPaths:(NSArray *)indexPaths

when inserting all other cells.

Interestingly, I also had a problem with 

- (void)deleteItemsAtIndexPaths:(NSArray *)indexPaths

when deleting the last cell. I did the same thing as before: just call reloadData when deleting the last cell.

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