Need -[UICollectionViewDelegate collectionView:willDisplayCell:forItemAtIndexPath:]

Originator:futuretap
Number:rdar://16070938 Date Originated:14-Feb-2014 06:55 PM
Status:Open Resolved:
Product:iOS SDK Product Version:7.0
Classification:Enhancement Reproducible:Not Applicable
 
Analogous to UITableView, I'd like to be separately informed when a cell is displayed on screen. This would be useful for lazy loading of content, for animations and various other purposes.

The data source method –collectionView:cellForItemAtIndexPath: doesn't really solve that purpose since it's (probably depending on the layout) called much earlier and for cells that might never be displayed in the visible area.

Also, there's -collectionView:didEndDisplayingCell:forItemAtIndexPath: but not the inverse callback. So also for symmetry reasons it would make sense to add this method.

Comments

Needed

Yes, this is needed to be correctly notified when a cell will display for lazy loading content, configuring cell appearance, and many other use cases.

By m.purland at April 29, 2014, 6:20 p.m. (reply...)

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