Wrong layout when rotating screen

[flowbe]

Description

We recently transitioned one of our floating panels from a UITableView to a UICollectionView using compositional layouts. After transitioning, we noticed that when rotating the screen (portrait > landscape > portrait), our layout would keep the landscape size. We didn't have this issue before.

Before	After

We tried updating both the collection view layout and the panel layout in viewWillTransition but nothing works. Could this be a bug related to collection views?

Expected behavior

Update the layout width accordingly to the orientation.

Actual behavior

When switching from landscape to portrait, the landscape width is kept.

Steps to reproduce

Code example that reproduces the issue

Our collection view layout looks like this:

let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .fractionalHeight(1))
let item = NSCollectionLayoutItem(layoutSize: itemSize)
item.contentInsets = NSDirectionalEdgeInsets(top: 5, leading: 5, bottom: 5, trailing: 5)
let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .estimated(100))
let group = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitem: item, count: 2)
group.contentInsets = NSDirectionalEdgeInsets(top: 0, leading: 15, bottom: 0, trailing: 15)
let section = NSCollectionLayoutSection(group: group)
let layout = UICollectionViewCompositionalLayout(section: section)

The complete code is available here.

How do you display panel(s)?

• Add as child view controllers
• Present modally

How many panels do you displays?

• 1
• 2+

Environment

Library version

2.5.0

Installation method

• CocoaPods
• Carthage
• Swift Package Manager

iOS version(s)

15.0

Xcode version

13.1

[flowbe]

After investigating, I noticed that the constraints on the content view are given a lower priority ($0.priority = .required - 1) which leads to this issue. When commenting the line, everything works fine. Why are you doing this?

[scenee]

@flowbe Could you please let me know whether your panel'sFloatingPanelController.contentMode is .static or . fitToBounds? The reason why the priority was set to .required - 1 is #359, which fixed #294. However #294 was an issue on . fitToBounds content mode. So if your panel’s content mode is .static, I’d like to the priory will be set to .required on .static content mode.

[flowbe]

Hi @scenee, we didn't change the contentMode variable so it is set to the default value, which is apparently .static

[scenee]

@flowbe Thanks for your information. I will change the priority on .static content mode.

[flowbe]

Hi @scenee, I saw that you made a PR for this issue, thanks a lot! Can you create a new release so I can update my project? Thanks a lot

[scenee]

I've released v2.5.1 now 👍 Thanks for your support and patient.