ios - UICollectionViewLayout when is layoutAttributesForItemAtIndexPath called -

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i'm subclassing uicollectionviewlayout, , layoutattributesforitematindexpath: method never called.

i know override layoutattributesforelementsinrect: well, i'd rather not have deal rect, lot simpler if deal index path.

if layoutattributesforitematindexpath: never called, whats point of it?

layoutattributesforitematindexpath: called in different scenarii, when add new cells collection view, when change layout, when reload specific index paths, etc.

you need implement it, though won't called in "default" scenario.


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