UICollectionViewLayout

The content from the WWDC sessions provides insights into various updates and features related to UICollectionViewLayout and other UIKit components. Here are some key points:

1. List Environment Trait: In the session "What’s new in UIKit" from WWDC 2024, it was mentioned that UI collection view list sections and UITableViews now have a list environment trait. This trait describes the style of the list that the view is in, allowing cells to be styled appropriately without needing to know the list style when configuring a cell. This is particularly useful for adapting the appearance of lists in different contexts, such as portrait and landscape orientations (What’s new in UIKit).

2. Compositional Layout: The same session discusses how compositional layout is used in the Files app to display lists in different styles based on the context, such as using an inset grouped appearance in portrait and a sidebar appearance in landscape (What’s new in UIKit).

3. Automatic Observation Tracking: In the session "What’s new in UIKit" from WWDC 2025, automatic observation tracking is highlighted as a feature that simplifies updating UI components like collection view cells. This feature allows UIKit to automatically track dependencies on observable objects, ensuring that any changes to the model's properties automatically update the UI (What’s new in UIKit).

These updates make it easier to manage and style collection views in UIKit, enhancing flexibility and reducing the need for manual configuration. If you have specific questions about these features or need more detailed information, feel free to ask!