ios - UICollectionView loads async image in different cells due to reload during async image downloading -

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when loading uicollectionview cells call method downloads image async.

during download however, collection view reloaded , when async image downloaded set in 2 different cells.

i have tried using nsoperationqueue in dealloc call cancelalloperations:, didn't work.

what best way cancel download , can provide sample code?

thanks.

i think best practice launch requests lazily need images, cache results, , have no expectations state of collection when request completes.

reloading collection not invalidating event request image in cell. scrolling away is, user might scroll back. make request, , in completion block request cache result , reloaditemsatindexpaths: on index path associated request.

my answer here, provides working code.


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