swiftui-liquid-glass

name swiftui-liquid-glass description Implement, review, or improve SwiftUI Liquid Glass effects for iOS 26+. Covers glassEffect modifier, GlassEffectContainer, glass button styles, glass toolbar/tab bar, static status badges vs interactive controls, morphing transitions, tinting, interactive glass, ToolbarSpacer, scrollEdgeEffectStyle, backgroundExtensionEffect, and availability gating. Use when asked about Liquid Glass, glass buttons, glassEffect, GlassEffectTransition, glassEffectID, glassEffectUnion, scroll edge effects, or adopting iOS 26 design. SwiftUI Liquid Glass Liquid Glass is the dynamic translucent material introduced across Apple platforms 26. Standard SwiftUI bars and presentations adopt it automatically when built with the current SDK. Reserve custom glass for functional controls and navigation surfaces, not general content backgrounds. See references/liquid-glass.md for the full API reference with additional examples. Contents Workflow Core API Summary Code Examples Common Mistakes Review Checklist References Workflow Choose the path that matches the request: 1. Implement a new feature with Liquid Glass Identify target surfaces (floating controls, custom bars, transient controls). Decide shape, prominence, and whether each element is a real control or static status. Wrap grouped glass elements in a GlassEffectContainer . Apply .glassEffect() after layout and appearance modifiers. Add .interactive() only to tappable/focusable elements. Add morphing transitions with glassEffectID(_:in:) where the view hierarchy changes with animation. Put glassEffectTransition(_:) on the inserted or removed glass child, not on the always-present container, and choose the style using Morphing & Transitions . Gate with if #available(iOS 26, *) and provide a fallback for earlier versions. 2. Improve an existing feature with Liquid Glass Find custom control or navigation backgrounds that can be replaced with .glassEffect() . Wrap sibling glass elements in GlassEffectContainer for blending and performance. Replace custom glass-like buttons with .buttonStyle(.glass) , .buttonStyle(.glassProminent) , or configurable styles such as .buttonStyle(.glass(.clear)) . Use .glass(_:) when the button needs a specific tint or variant; reserve .glassProminent for high-emphasis primary actions. Add morphing transitions where animated insertion/removal occurs. 3. Review existing Liquid Glass usage Trace each effect through content/control ownership, layout order, container scope, interactivity, transitions, availability, accessibility settings, and fallback. Restore the same UI fixture and rerun the checklist after each correction. Core API Summary glassEffect(_:in:) Applies Liquid Glass behind a view. Default: .regular variant in a Capsule shape. nonisolated func glassEffect ( _ glass : Glass = .regular, in shape : some Shape = DefaultGlassEffectShape () ) -> some View Glass struct Property / Method Purpose .regular Standard glass material .clear Clear variant; add dimming/contrast treatment when legibility needs it .identity No visual effect (pass-through) .tint(_:) Add a color tint for prominence .interactive(_:) React to touch and pointer interactions Chain them: .regular.tint(.blue).interactive() GlassEffectContainer Wraps multiple glass views for shared rendering, blending, and morphing. GlassEffectContainer (spacing: 24 ) { // child views with .glassEffect() } The spacing controls when nearby glass shapes begin to blend. Match or exceed the interior layout spacing so shapes merge during animated transitions but remain separate at rest. Morphing & Transitions Modifier Purpose glassEffectID(_:in:) Stable identity for morphing during view hierarchy changes glassEffectUnion(id:namespace:) Merge multiple views into one glass shape glassEffectTransition(_:) Control how glass appears/disappears Transition decision: use .matchedGeometry for nearby effects inside the container's spacing; use .materialize for distant insertion/removal or when no geometry match should occur; use .identity only when no transition animation is wanted. Button Styles Button ( "Action" ) { } .buttonStyle(.glass) // standard glass button Button ( "Primary" ) { } .buttonStyle(.glassProminent) // prominent glass button Button ( "Media" ) { } .buttonStyle(.glass(.clear)) // configurable variant; verify contrast Related iOS 26 APIs API Use scrollEdgeEffectStyle Configure a scroll boundary's visual treatment. backgroundExtensionEffect Extend one background under safe-area edges with mirrored blur. ToolbarSpacer Create a visual break between toolbar items. See the corresponding sections in references/liquid-glass.md for signatures and examples. Code Examples Glass button with availability gate if #available ( iOS 26 , * ) { Button ( "Show Status" ) { showStatusDetails() } .buttonStyle(.glass) } else { Button ( "Show Status" ) { showStatusDetails() } .buttonStyle(.bordered) } Grouped glass shapes in a container let symbols = [ "pencil" , "eraser.fill" , "lasso" ] GlassEffectContainer (spacing: 24 ) { HStack (spacing: 24 ) { ForEach (symbols, id: \. self ) { symbol in Image (systemName: symbol) .frame(width: 56 , height: 56 ) .glassEffect() } } } Nearby morphing transition @State private var isExpanded = false @Namespace private var ns var body: some View { GlassEffectContainer (spacing: 40 ) { HStack (spacing: 40 ) { Image (systemName: "pencil" ) .frame(width: 80 , height: 80 ) .glassEffect() .glassEffectID( "pencil" , in: ns) if isExpanded { Image (systemName: "eraser.fill" ) .frame(width: 80 , height: 80 ) .glassEffect() .glassEffectID( "eraser" , in: ns) .glassEffectTransition(.matchedGeometry) } } } Button ( "Toggle" ) { withAnimation { isExpanded.toggle() } } .buttonStyle(.glass) } Unioning views into a single glass shape @Namespace private var ns GlassEffectContainer (spacing: 20 ) { HStack (spacing: 20 ) { ForEach (items.indices, id: \. self ) { i in Image (systemName: items[i]) .frame(width: 80 , height: 80 ) .glassEffect() .glassEffectUnion(id: i < 2 ? "group1" : "group2" , namespace: ns) } } } Tinted glass icon control struct GlassIconControl : View { let icon: String let tint: Color let action: () -> Void var body: some View { Button (action: action) { Image (systemName: icon) .font(.title2) .padding() } .buttonStyle(.glass(.regular.tint(tint))) } } Clear glass action over bright content if #available ( iOS 26 , * ) { ZStack { Capsule () .fill(.black.opacity( 0.28 )) Button { playRecap() } label: { Label ( "Play" , systemImage: "play.fill" ) .font(.headline) .padding(.horizontal, 8 ) } .buttonStyle(.glass(.clear)) } .fixedSize() } else { Button ( "Play" , systemImage: "play.fill" ) { playRecap() } .buttonStyle(.borderedProminent) } Use clear glass only when the background still leaves labels and symbols readable. On bright or busy backgrounds, add a subtle dimming layer or choose a more opaque button style. Static status count, not a toolbar control VStack (spacing: 8 ) { Text ( "24" ) .font(.headline.monospacedDigit()) .accessibilityLabel( "24 options expiring" ) Text ( "Options Expiring" ) .font(.subheadline) .foregroundStyle(.secondary) } // Keep read-only status out of toolbar control slots and do not add .interactive(). Common Mistakes Mistake Fix Glass decorates static content Keep it in the controls/navigation layer. Read-only status uses .interactive() or an action slot Present status as content, or make the whole badge one real accessible action. Related effects use nested containers Use one GlassEffectContainer per related blending/morphing group. .glassEffect() precedes padding/frame/style Apply layout and appearance first, then glass. Custom effects assume default accessibility settings Test Reduce Transparency, Reduce Motion, contrast, and legibility. No pre-iOS 26 path Gate the effect and preserve a functional fallback. Review Checklist Availability : if #available(iOS 26, *) present with fallback UI. Container : Multiple glass views wrapped in GlassEffectContainer . Modifier order : .glassEffect() applied after layout/appearance modifiers. Interactivity : .interactive() used only where user interaction exists. Status vs action : Static counts/status are not toolbar controls and do not expose press/hover affordance. Transitions : glassEffectID used with @Namespace for morphing animations. Transition type : .matchedGeometry for nearby effects; .materialize for distant ones, applied to the conditional glass child. Consistency : Shapes, tints, and spacing are uniform across related elements. Performance : Glass effects are limited in number; container used for grouping. Accessibility : Tested with Reduce Transparency and Reduce Motion enabled. Button styles : Standard .glass , .glassProminent , or configurable .glass(_:) used for buttons; .glass(_:) is primary when a tint or clear variant is required. Clear glass contrast : Clear glass over bright content has a dimming/contrast treatment or uses a more legible style. Concurrency : IDs passed to glassEffectID / glassEffectUnion are Sendable ; MainActor-annotated Liquid Glass APIs stay in SwiftUI UI code. References Full API guide: references/liquid-glass.md Apple docs: Applying Liquid Glass to custom views Apple docs: Adopting Liquid Glass