swift - UICollectionView - iOS 10 - crash on iPhone 6 Plus simulator but works on real device

Question

I've created an UICollectionView that works fine on small devices like iPhone 5s/SE/6/6s/7 on both simulator and real device, but I have a strange situation when it comes about iPhone 6Plus, iPhone 7Plus and any iPad version. It works fine on real device, but it crashes in simulator with the following error:

Assertion failure in -[_UIFlowLayoutSection computeLayoutInRect:forSection:invalidating:invalidationContext:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.5.2/UIFlowLayoutSupport.m:823

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'UICollectionViewFlowLayout internal error'

What I found out so far is that if I remove the estimatedItemSize it works fine but the auto-layout doesn't anymore, but if I have that enabled it crashes in simulator.

I am using the latest Xcode version and iOS 10.

Any ideas why it's crashing?

Answer 1

Calling invalidateLayout before layout is a workaround for this issue.

In a UIViewController subclass:

override func viewWillLayoutSubviews() {
    super.viewWillLayoutSubviews()
    collectionView.collectionViewLayout.invalidateLayout()
}

or in a UIView subclass:

override func layoutSubviews() {
    super.layoutSubviews()
    collectionView.collectionViewLayout.invalidateLayout()
}