abanoub-ashraf/ios26-liquid-glass

iOS 26 Liquid Glass Design System

Liquid Glass is Apple's new universal design language introduced at WWDC25 (June 2025). It features a dynamic material that combines optical glass properties with fluid animations, creating a layered, translucent UI that adapts to content and interactions.

Overview

Liquid Glass:

• Blurs content behind it
• Reflects color and light from surroundings
• Reacts to touch and pointer interactions in real-time
• Morphs between states with fluid animations

Available on: iOS 26, iPadOS 26, macOS Tahoe 26, watchOS 26, tvOS 26, visionOS 26

Basic Glass Effects

Apply Glass to Any View

import SwiftUI

// Basic glass effect (capsule shape by default)
Text("Hello, World!")
    .font(.title)
    .padding()
    .glassEffect()

// Custom shape
Text("Hello, World!")
    .font(.title)
    .padding()
    .glassEffect(in: .rect(cornerRadius: 16))

// Tinted and interactive
Text("Tap Me")
    .font(.title)
    .padding()
    .glassEffect(.regular.tint(.orange).interactive())

Glass Button Styles

// Standard glass button
Button("Action") { }
    .buttonStyle(.glass)

// Prominent glass button (more visible)
Button("Primary Action") { }
    .buttonStyle(.glassProminent)

// Configured glass button
Button("Custom") { }
    .buttonStyle(.glass(.regular.tint(.blue)))

Glass Variants

// Regular glass (default)
.glassEffect(.regular)

// With tint color
.glassEffect(.regular.tint(.blue))

// Interactive (responds to touch/hover)
.glassEffect(.regular.interactive())

// Combined
.glassEffect(.regular.tint(.purple).interactive())

Glass Effect Containers

Use GlassEffectContainer when multiple views need glass effects - enables blending and morphing.

Basic Container

GlassEffectContainer(spacing: 40) {
    HStack(spacing: 40) {
        Image(systemName: "pencil")
            .frame(width: 80, height: 80)
            .font(.system(size: 36))
            .glassEffect()
        
        Image(systemName: "eraser.fill")
            .frame(width: 80, height: 80)
            .font(.system(size: 36))
            .glassEffect()
    }
}

Blending Effects

The container's spacing controls when glass effects blend together:

• Larger spacing = effects blend sooner
• When views are closer than container spacing, glass shapes merge

// Effects will blend when items are within 40pt
GlassEffectContainer(spacing: 40) {
    HStack(spacing: 20) { // Closer than container spacing
        ForEach(items) { item in
            ItemView(item: item)
                .glassEffect()
        }
    }
}

Unified Glass Groups

Use glassEffectUnion to combine multiple views into a single glass shape:

@Namespace private var namespace

GlassEffectContainer(spacing: 20) {
    HStack(spacing: 20) {
        ForEach(symbols.indices, id: \.self) { index in
            Image(systemName: symbols[index])
                .frame(width: 80, height: 80)
                .font(.system(size: 36))
                .glassEffect()
                // First two share one glass, last two share another
                .glassEffectUnion(id: index < 2 ? "group1" : "group2", namespace: namespace)
        }
    }
}

Morphing Transitions

Glass effects can morph into each other during view transitions.

Basic Morphing

@State private var isExpanded = false
@Namespace private var namespace

GlassEffectContainer(spacing: 40) {
    HStack(spacing: 40) {
        Image(systemName: "scribble.variable")
            .frame(width: 80, height: 80)
            .glassEffect()
            .glassEffectID("pencil", in: namespace)
        
        if isExpanded {
            Image(systemName: "eraser.fill")
                .frame(width: 80, height: 80)
                .glassEffect()
                .glassEffectID("eraser", in: namespace)
        }
    }
}

Button("Toggle") {
    withAnimation {
        isExpanded.toggle()
    }
}
.buttonStyle(.glass)

Transition Types

// Matched geometry (default for nearby elements)
.glassEffectTransition(.matchedGeometry)

// Materialize (fade in/out for distant elements)
.glassEffectTransition(.materialize)

TabView with Liquid Glass

Auto-Minimizing Tab Bar

TabView {
    Tab("Workouts", systemImage: "dumbbell.fill") {
        WorkoutsView()
    }
    
    Tab("Exercises", systemImage: "figure.strengthtraining.traditional") {
        ExercisesView()
    }
}
.tabBarMinimizeBehavior(.onScrollDown)  // Minimizes when scrolling

Tab Bar Bottom Accessory

Add persistent controls above the tab bar (like music player controls):

TabView {
    // tabs...
}
.tabViewBottomAccessory {
    // This view appears above the tab bar
    NowPlayingMiniPlayer()
}

Search Tab (Floating Button)

TabView {
    Tab("Home", systemImage: "house") {
        HomeView()
    }
    
    // Creates a floating search button in bottom-right
    Tab("Search", systemImage: "magnifyingglass", value: .search, role: .search) {
        SearchView()
    }
}

Navigation with Liquid Glass

Navigation bars automatically adopt Liquid Glass in iOS 26:

NavigationStack {
    List {
        // Content scrolls under glass navigation bar
    }
    .navigationTitle("Items")
}

Toolbar Items

.toolbar {
    ToolbarItem(placement: .primaryAction) {
        Button("Add", systemImage: "plus") { }
    }
}
// Toolbar buttons automatically get glass treatment

Floating Action Buttons

Create floating buttons that fit the Liquid Glass design:

ZStack(alignment: .bottomTrailing) {
    // Main content
    List { /* ... */ }
    
    // Floating glass button
    Button(action: addItem) {
        Label("Add", systemImage: "plus")
            .labelStyle(.iconOnly)
            .font(.title2)
            .padding()
    }
    .glassEffect(.regular.interactive())
    .padding([.bottom, .trailing], 16)
}

Performance Optimization

Best Practices

// ✅ Use containers for multiple effects
GlassEffectContainer {
    ForEach(items) { item in
        ItemView(item: item)
            .glassEffect()
    }
}

// ❌ Avoid too many standalone effects
ForEach(items) { item in
    ItemView(item: item)
        .glassEffect()  // Each creates separate render pass
}

Limit Glass Effects

• Don't overuse glass effects on screen simultaneously
• Group related glass elements in containers
• Use glass sparingly for key UI elements
• Profile with Instruments → SwiftUI performance tools

Opting Out of Liquid Glass

If you need more time to adopt, you can temporarily opt out:

// In your app's Info.plist or build settings
// Set UIDesignRequiresCompatibilityMode = YES

// Or programmatically for specific views
.preferredDesignStyle(.compatible)  // Use legacy style

Note: This escape hatch is temporary and will be removed in a future iOS version.

Design Principles

Layered Design

Liquid Glass encourages layered UIs:

1. Background content - scrollable, full of information
2. Glass overlays - navigation, controls, key actions
3. Content shows through - blur creates depth

When to Use Glass

• Navigation bars and tab bars (automatic)
• Floating action buttons
• Toolbars and control groups
• Modal sheets and popovers
• Key interactive elements

When NOT to Use Glass

• Every button (too much glass is overwhelming)
• Static text labels
• Dense content areas
• Performance-critical views

Migration Checklist

• [ ] Recompile with Xcode 26 (automatic glass for standard components)
• [ ] Review tab bar - does content scroll underneath?
• [ ] Check floating buttons - convert to .glassEffect()
• [ ] Test morphing transitions for dynamic content
• [ ] Profile performance with Instruments
• [ ] Review custom components - add glass where appropriate
• [ ] Test on all supported platforms (iOS, iPadOS, macOS, etc.)

Related WWDC25 Sessions

• What's new in SwiftUI - Overview of Liquid Glass
• Build a SwiftUI app with the new design - Deep dive into adoption
• Landmarks: Building an app with Liquid Glass - Sample code walkthrough
• Optimize SwiftUI performance with Instruments - Performance profiling