SwiftUI Presentations

Guidance for sheets, detents, popovers, full-screen covers, and how each presentation adapts across size classes and window shapes — including the iOS 27 reality that iPhone apps resize, so adaptation applies everywhere.

When to Use

Use this skill when:

• Choosing between a sheet, popover, full-screen cover, inspector, or second window
• Building resizable sheets with detents (.medium, .fraction, .height, custom)
• A popover shows as a sheet on iPhone and you need to control that adaptation
• A medium-detent sheet unexpectedly goes full screen in landscape
• Sizing sheets on iPad and Mac (presentationSizing, iOS 18)
• Building maps-style non-modal sheets where the background stays interactive
• Anchoring a popover to a button or toolbar item correctly

Example Prompts

• "How do I make a half-height sheet with presentationDetents?"
• "Why does my popover show as a sheet on iPhone?"
• "My sheet with a medium detent goes full screen in landscape"
• "How do I keep the map interactive behind a low sheet?"
• "How do I size a sheet on iPad like a form?"
• "How do I stop swipe-to-dismiss on my editing sheet without trapping users?"

What This Skill Provides

• Presentation-choice table – by role: sheet vs popover vs cover vs dialog vs inspector vs second window
• Detent patterns – presentationDetents with selection tracking, drag indicator, background interaction, content-interaction priority, and the landscape full-screen-cover trap
• iOS 18 sheet sizing – .form, .page, .fitted for large windows
• Popover anchoring and adaptation – attachmentAnchor/arrowEdge mechanics, default iPhone sheet adaptation, presentationCompactAdaptation, and why a wide iPhone window at iOS 27 still adapts like an iPhone
• Adaptation discipline – one state model with system adaptation, modifiers on the presented content, and why system containers beat custom overlay presentations for indirect input

Related

• Toolbars – Cancel/Done placement rules for sheet toolbars
• SwiftUI Layout – the size-class model that drives presentation adaptation
• SwiftUI Navigation – navigation containers that presentations layer on top of
• UIKit Modernization – iPhone Mirroring's indirect-input model, which standard presentation containers handle correctly and custom overlays must wire up themselves