UICollectionViewFlowLayout doesn't correctly animate self-sizing cells' sizes

Originator:lap.felix
Number:rdar://41219127 Date Originated:June 18 2018, 3:01 PM
Status:Open Resolved:
Product:iOS + SDK Product Version:12.0 Beta 1
Classification:UIKit Reproducible:Always
 
Summary:
UICollectionViewFlowLayout cannot be used to animate the resizing of self-sizing cells. The anima

Steps to Reproduce:
Have self-sizing cells
Resize them and call [performBatchUpdates:completion:]

Expected Results:
The cells should resize correctly

Actual Results:
All the cells animate to a size of 50,50 (arranged in a grid) and then after the animation, the cells instantly (with no animation) get the correct size and layout.

Version:
12.0 Beta 1

Notes:
Because of this we need to use a custom UICollectionViewLayout (not a subclass of UICollectionViewFlowLayout) and we miss out on some nice features of UICollectionViewFlowLayout.

Configuration:

Sample project: https://dsc.cloud/felix/UICollectionViewStruggle.zip

Comments


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