SwiftUI Sheet, Modal & Bottom Sheet — Complete 2026 Field Guide

Basic Sheet Presentation

Sheets work with two binding patterns. Boolean for "is this view showing", or Identifiable item for "show a sheet with this data". Prefer the item form when the sheet needs data to render — it avoids the optional unwrapping dance.

struct ContentView: View {
  @State private var selectedTask: Task?

  var body: some View {
    List(tasks) { task in
      Button(task.title) { selectedTask = task }
    }
    .sheet(item: $selectedTask) { task in
      TaskDetailView(task: task)
    }
  }
}

Bottom Sheets with .presentationDetents

The iOS 16+ presentationDetents modifier converts any sheet into a resizable bottom sheet. Pass an array of heights — users can drag between them. This is the same API that powers Maps and Wallet.

• .medium = ~50% of screen, .large = full sheet
• .fraction(0.3) for custom heights (iOS 16+)
• .height(200) for fixed-point heights
• .presentationDragIndicator(.visible) shows the grab handle
• .presentationBackgroundInteraction(.enabled(upThrough: .medium)) lets users tap behind the sheet at smaller detents

.sheet(isPresented: $showFilters) {
  FiltersView()
    .presentationDetents([.fraction(0.3), .medium, .large])
    .presentationDragIndicator(.visible)
    .presentationBackgroundInteraction(.enabled(upThrough: .medium))
}

Full-Screen Covers (Onboarding, Paywalls)

.fullScreenCover takes over the entire window and requires programmatic dismissal. Use it for onboarding flows, paywalls, and any state where the user MUST complete or explicitly close. Sheets are for non-blocking UX.

.fullScreenCover(isPresented: $showPaywall) {
  PaywallView()
    .interactiveDismissDisabled(!hasFreeTrialEnded)
}

Common Bugs and Fixes

Three modal bugs you'll hit in production:

• Sheet ignores @State changes — bind to @State on the parent, never inside the sheet content
• Detents jump on first present — set .presentationDetents BEFORE the sheet first appears
• Sheet inside NavigationStack loses navigation context — wrap the sheet content in its own NavigationStack
• Keyboard pushes sheet content offscreen — use .presentationContentInteraction(.resizes) or scroll inside

Frequently Asked Questions