liquid-glass-design

Documento original del Skill

Contenido del repositorio de origen con títulos, ejemplos, código, tablas, enlaces e imágenes preservados.

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