apple-text-dynamic-type

To scale custom fonts for Dynamic Type, use UIFontMetrics to map non-system fonts to a specific text style. This ensures your custom typography adapts to user accessibility size preferences while maintaining layout integrity across UIKit.

Dynamic Type works across SwiftUI, UIKit, and AppKit, though macOS has specific constraints. This skill provides cross-platform guidance to apply semantic font scaling and handle size-category changes consistently across iOS and macOS environments.

The best way to handle accessibility text sizes in SwiftUI is using the @ScaledMetric property wrapper. This dynamically scales custom fonts alongside system text styles, ensuring your UI adapts seamlessly to user accessibility text preferences.

Text clipping and overflow at large accessibility sizes occur when layouts are not validated against AX1 through AX5 size categories. Testing your interface at these extreme accessibility sizes is required to prevent dynamic text from breaking your layout constraints.

UIFontMetrics adjusts text scaling by creating a metrics object for a target text style and applying it to your custom font. This maps your non-system font to the system's semantic font scaling behavior for accurate dynamic type updates.

Use semantic fonts whenever possible to ensure automatic Dynamic Type updates without manual calculations. Employ custom fonts only when necessary, pairing them with UIFontMetrics or @ScaledMetric to achieve responsive text sizing that respects accessibility settings.