Invalidating a UICollectionViewFlowLayout causes glitches when rendering the collection view items

Originator:raphaelcruzeiro
Number:rdar://28115029 Date Originated:01 sep 2016
Status:Open Resolved:No
Product:iOS Product Version:10
Classification:Major bug Reproducible:Always
 
Area:
UIKit

Summary:
Invalidating the layout of a collection view (to create custom static headers for example) causes glitches to appear on the collection view items while scrolling. This did not happen on the previous versions of the SDK.

Steps to Reproduce:
- Run the attached project. 
- Scroll through the collection view
- Notice how cells will overlap while scrolling before being drawn at the correct position

Expected Results:
The items should be rendered correctly as they were on the previous versions of the SDK.

Actual Results:
Cells will overlap while scrolling before being drawn at the correct position

Version:
iOS 10.0 (14A5346a)

Notes:
Project build with Xcode 8 beta 6

Configuration:
iPhone 6S

Attachments:
'CollectionViewLayoutExample.zip' was successfully uploaded.

Comments


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