how autolayout works

Auto Layout is a system used in Apple's development frameworks, such as UIKit, to create responsive and adaptive user interfaces. It allows developers to define rules and constraints for how UI elements should be positioned and sized relative to each other and the parent view. This ensures that the layout adapts to different screen sizes, orientations, and content sizes.

In the context of the WWDC sessions, Auto Layout is discussed in relation to dynamic type and accessibility. For example, in the session "Get started with Dynamic Type," it is mentioned how using UIStackView in UIKit can help manage layout changes when text size changes, especially for accessibility purposes. The stack view automatically adjusts the layout of subviews vertically or horizontally based on the content size category, which can be particularly useful for handling dynamic type changes.

Additionally, in the session "What’s new in UIKit," automatic trait tracking is introduced, which simplifies the process of handling layout changes by automatically tracking and responding to trait changes, such as size class changes, without the need for manual registration.

For more detailed information on how Auto Layout works with dynamic type and accessibility, you can refer to the session Get started with Dynamic Type (06:00) and What’s new in UIKit (06:02).