UICollectionView Self-Sizing Supplementary View Layout Issue

Originator:bryn.bodayle
Number:rdar://29630641 Date Originated:12/12/16
Status:Open Resolved:
Product:iOS+SDK Product Version:
Classification: Reproducible:Always
 
Area:
UIKit

Summary:
When trying to use self-sizing supplementary views in a UICollectionViewLayout subclass, the supplementary views will have an incorrect layout when scrolling down.

Steps to Reproduce:
1. Download the sample project VCVBug.zip here or attached to this issue.
https://www.dropbox.com/s/d6jkhsdduyx8aqx/VCVBug.zip?dl=0
2. Build and run the project on any device/simulator and any iOS version, with iOS 10 prefetchingEnabled = true or = false.
3. Scroll down and notice that the red section headers are incorrectly sized. 
4. Scroll down and then back up so that the incorrectly sized section headers go off screen and then come back on and then they are sized correctly.


Expected Results:
Self-sizing supplementary views should layout correctly when using Auto Layout just as their UICollectionViewCell counterparts do.

Actual Results:
Self-sizing supplementary views often have incorrect frames when scrolling.

Version:
iOS 9-10

Notes:


Configuration:
Any iPhone model or simulator

Comments


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