— name: liquid-glass-design description: iOS 26 Liquid Glass design system — dynamic glass material with blur, reflection, and interactive morphing for SwiftUI, UIKit, and WidgetKit. — # Liquid Glass Design System (iOS 26) Patterns for implementing Apple's Liquid Glass — a dynamic material that blurs content behind it, reflects color and light from surrounding content, and reacts to touch and pointer interactions. Covers SwiftUI, UIKit, and WidgetKit integration. ## When to Activate – Building or updating apps for iOS 26+ with the new design language – Implementing glass-style buttons, cards, toolbars, or containers – Creating morphing transitions between glass elements – Applying Liquid Glass effects to widgets – Migrating existing blur/material effects to the new Liquid Glass API ## Core Pattern — SwiftUI ### Basic Glass Effect The simplest way to add Liquid Glass to any view: “`swift Text("Hello, World!") .font(.title) .padding() .glassEffect() // Default: regular variant, capsule shape “` ### Customizing Shape and Tint “`swift Text("Hello, World!") .font(.title) .padding() .glassEffect(.regular.tint(.orange).interactive(), in: .rect(cornerRadius: 16.0)) “` Key customization options: – `.regular` — standard glass effect – `.tint(Color)` — add color tint for prominence – `.interactive()` — react to touch and pointer interactions – Shape: `.capsule` (default), `.rect(cornerRadius:)`, `.circle` ### Glass Button Styles “`swift Button("Click Me") { /* action */ } .buttonStyle(.glass) Button("Important") { /* action */ } .buttonStyle(.glassProminent) “` ### GlassEffectContainer for Multiple Elements Always wrap multiple glass views in a container for performance and morphing: “`swift GlassEffectContainer(spacing: 40.0) { HStack(spacing: 40.0) { Image(systemName: "scribble.variable") .frame(width: 80.0, height: 80.0) .font(.system(size: 36)) .glassEffect() Image(systemName: "eraser.fill") .frame(width: 80.0, height: 80.0) .font(.system(size: 36)) .glassEffect() } } “` The `spacing` parameter controls merge distance — closer elements blend their glass shapes together. ### Uniting Glass Effects Combine multiple views into a single glass shape with `glassEffectUnion`: “`swift @Namespace private var namespace GlassEffectContainer(spacing: 20.0) { HStack(spacing: 20.0) { ForEach(symbolSet.indices, id: \.self) { item in Image(systemName: symbolSet[item]) .frame(width: 80.0, height: 80.0) .glassEffect() .glassEffectUnion(id: item < 2 ? "group1" : "group2", namespace: namespace) } } } “` ### Morphing Transitions Create smooth morphing when glass elements appear/disappear: “`swift @State private var isExpanded = false @Namespace private var namespace GlassEffectContainer(spacing: 40.0) { HStack(spacing: 40.0) { Image(systemName: "scribble.variable") .frame(width: 80.0, height: 80.0) .glassEffect() .glassEffectID("pencil", in: namespace) if isExpanded { Image(systemName: "eraser.fill") .frame(width: 80.0, height: 80.0) .glassEffect() .glassEffectID("eraser", in: namespace) } } } Button("Toggle") { withAnimation { isExpanded.toggle() } } .buttonStyle(.glass) “` ### Extending Horizontal Scrolling Under Sidebar To allow horizontal scroll content to extend under a sidebar or inspector, ensure the `ScrollView` content reaches the leading/trailing edges of the container. The system automatically handles the under-sidebar scrolling behavior when the layout extends to the edges — no additional modifier is needed. ## Core Pattern — UIKit ### Basic UIGlassEffect “`swift let glassEffect = UIGlassEffect() glassEffect.tintColor = UIColor.systemBlue.withAlphaComponent(0.3) glassEffect.isInteractive = true let visualEffectView = UIVisualEffectView(effect: glassEffect) visualEffectView.translatesAutoresizingMaskIntoConstraints = false visualEffectView.layer.cornerRadius = 20 visualEffectView.clipsToBounds = true view.addSubview(visualEffectView) NSLayoutConstraint.activate([ visualEffectView.centerXAnchor.constraint(equalTo: view.centerXAnchor), visualEffectView.centerYAnchor.constraint(equalTo: view.centerYAnchor), visualEffectView.widthAnchor.constraint(equalToConstant: 200), visualEffectView.heightAnchor.constraint(equalToConstant: 120) ]) // Add content to contentView let label = UILabel() label.text = "Liquid Glass" label.translatesAutoresizingMaskIntoConstraints = false visualEffectView.contentView.addSubview(label) NSLayoutConstraint.activate([ label.centerXAnchor.constraint(equalTo: visualEffectView.contentView.centerXAnchor), label.centerYAnchor.constraint(equalTo: visualEffectView.contentView.centerYAnchor) ]) “` ### UIGlassContainerEffect for Multiple Elements “`swift let containerEffect = UIGlassContainerEffect() containerEffect.spacing = 40.0 let containerView = UIVisualEffectView(effect: containerEffect) let firstGlass = UIVisualEffectView(effect: UIGlassEffect()) let secondGlass = UIVisualEffectView(effect: UIGlassEffect()) containerView.contentView.addSubview(firstGlass) containerView.contentView.addSubview(secondGlass) “` ### Scroll Edge Effects “`swift scrollView.topEdgeEffect.style = .automatic scrollView.bottomEdgeEffect.style = .hard scrollView.leftEdgeEffect.isHidden = true “` ### Toolbar Glass Integration “`swift let favoriteButton = UIBarButtonItem(image: UIImage(systemName: "heart"), style: .plain, target: self, action: #selector(favoriteAction)) favoriteButton.hidesSharedBackground = true // Opt out of shared glass background “` ## Core Pattern — WidgetKit ### Rendering Mode Detection “`swift struct MyWidgetView: View { @Environment(\.widgetRenderingMode) var renderingMode var body: some View { if renderingMode == .accented { // Tinted mode: white-tinted, themed glass background } else { // Full color mode: standard appearance } } } “` ### Accent Groups for Visual Hierarchy “`swift HStack { VStack(alignment: .leading) { Text("Title") .widgetAccentable() // Accent group Text("Subtitle") // Primary group (default) } Image(systemName: "star.fill") .widgetAccentable() // Accent group } “` ### Image Rendering in Accented Mode “`swift Image("myImage") .widgetAccentedRenderingMode(.monochrome) “` ### Container Background “`swift VStack { /* content */ } .containerBackground(for: .widget) { Color.blue.opacity(0.2) } “` ## Key Design Decisions | Decision | Rationale | |———-|———–| | GlassEffectContainer wrapping | Performance optimization, enables morphing between glass elements | | `spacing` parameter | Controls merge distance — fine-tune how close elements must be to blend | | `@Namespace` + `glassEffectID` | Enables smooth morphing transitions on view hierarchy changes | | `interactive()` modifier | Explicit opt-in for touch/pointer reactions — not all glass should respond | | UIGlassContainerEffect in UIKit | Same container pattern as SwiftUI for consistency | | Accented rendering mode in widgets | System applies tinted glass when user selects tinted Home Screen | ## Best Practices – **Always use GlassEffectContainer** when applying glass to multiple sibling views — it enables morphing and improves rendering performance – **Apply `.glassEffect()` after** other appearance modifiers (frame, font, padding) – **Use `.interactive()`** only on elements that respond to user interaction (buttons, toggleable items) – **Choose spacing carefully** in containers to control when glass effects merge – **Use `withAnimation`** when changing view hierarchies to enable smooth morphing transitions – **Test across appearances** — light mode, dark mode, and accented/tinted modes – **Ensure accessibility contrast** — text on glass must remain readable ## Anti-Patterns to Avoid – Using multiple standalone `.glassEffect()` views without a GlassEffectContainer – Nesting too many glass effects — degrades performance and visual clarity – Applying glass to every view — reserve for interactive elements, toolbars, and cards – Forgetting `clipsToBounds = true` in UIKit when using corner radii – Ignoring accented rendering mode in widgets — breaks tinted Home Screen appearance – Using opaque backgrounds behind glass — defeats the translucency effect ## When to Use – Navigation bars, toolbars, and tab bars with the new iOS 26 design – Floating action buttons and card-style containers – Interactive controls that need visual depth and touch feedback – Widgets that should integrate with the system's Liquid Glass appearance – Morphing transitions between related UI states