Custom collection view layout not animating frame properly

Originator:daniel.johns
Number:rdar://21672623 Date Originated:July 3, 2015
Status:Open Resolved:
Product:iOS SDK Product Version:8.4
Classification:UI/Usability Reproducible:Always
 
Summary:
I have a custom collection view layout that place views on top of each other. All but one view is collapsed to a reduced height. When a cell is tapped that becomes the full height view and all cells should smoothly animate to their new positions. The expanding view animates properly but the shrinking view immediately jumps to its reduced size then animates into position. See the gif in the readme for a demonstration.

Github repo with the project to demonstrate: https://github.com/civatrix/StackCollectionViewLayout

Steps to Reproduce:
1. Run project on any device or simulator
2. Tap "Cell 1"
3. Tap "Cell 0"

Expected Results:
After tapping "Cell 1", "Cell 0" should animate it's height change along side "Cell 1"
After tapping "Cell 0", "Cell 1" should animate it's height change along side "Cell 0"

Actual Results:
After tapping "Cell 1", "Cell 0" immeditaly becomes it's new collapsed height
After tapping "Cell 0", "Cell 1" immeditaly becomes it's new collapsed height and moves to it's final position

Version:
Any

Notes:
All final cell frames are correct, it's just the animation that is the issue

Configuration:
Any

Attachments:

Comments


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