I have a very simple custom collection view layout that supports self-sizing. When a cell is selected, I expand the cell by modifying its constraints. This change (and the resulting effect on the collection view layout) is animated using [self.collectionView.collectionViewLayout invalidateLayout] followed by [self.collectionView layoutIfNeeded] within an animation closure.
When you first tap on a cell, it expands smoothly as expected. When you tap on it again to contract it, however, its content jumps before it shrinks again. How can I fix this?
For what it’s worth, I’ve noticed that neither UICollectionViewFlowLayout nor UICollectionViewCompositionalLayout have this issue, which suggests I’m doing self-sizing incorrectly.
Here’s a screen recording demonstrating the issue. I’ve also put together a minimal sample project.
I’m using Xcode 26.2 and iOS 26.2.1.