UICollectionView - resizing cells on device rotate - Swift

Question

I\'ve created a UICollectionView, so that I can arrange views into neat columns. I\'d like there to be a single column on devices > 500 pixels wide.

In order to achi

Answer 1

traitCollectionDidChange method might be used as well instead of viewWillLayoutSubviews:

override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
    super.traitCollectionDidChange(previousTraitCollection)

    guard let previousTraitCollection = previousTraitCollection, traitCollection.verticalSizeClass != previousTraitCollection.verticalSizeClass ||
        traitCollection.horizontalSizeClass != previousTraitCollection.horizontalSizeClass else {
            return
    }

    if traitCollection.horizontalSizeClass == .regular && traitCollection.verticalSizeClass == .regular {
        // iPad portrait and landscape
        // do something here...
    }
    if traitCollection.horizontalSizeClass == .compact && traitCollection.verticalSizeClass == .regular {
        // iPhone portrait
        // do something here...
    }
    if traitCollection.horizontalSizeClass == .regular && traitCollection.verticalSizeClass == .compact {
        // iPhone landscape
        // do something here...
    }
    collectionView?.collectionViewLayout.invalidateLayout()
    collectionView?.reloadData()
}