# Skeleton

A pulsing placeholder shape shown while content loads.

Skeleton is an open-source mobile component from suiss/uim for React Native and Expo, with SwiftUI and Jetpack Compose versions built from the same design tokens. The @esuiss/uim CLI copies its source into your project, so you own the code.

Source: https://uim.suiss.app/docs/components/skeleton

![Preview](https://uim.suiss.app/previews/components-skeleton--default.light.webp)

```tsx
import { Skeleton } from "@/components/ui/skeleton"

export function SkeletonExample() {
  return (
    <Skeleton className="h-4 w-48" />
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct SkeletonExample: View {
  var body: some View {
    Skeleton()
      .frame(width: 192, height: 16)
  }
}
```

```kotlin
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.width
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Skeleton

@Composable
fun SkeletonExample() {
    Skeleton(Modifier.width(192.dp).height(16.dp))
}
```

`Skeleton` is a Reanimated `View` with a rounded background whose opacity pulses between 1 and 0.5 on a loop. It has no fixed size; you shape it with classes to match the content it stands in for.

## Installation

```bash title="Terminal"
npx @esuiss/uim@latest add skeleton
```

```bash title="Terminal"
npx @esuiss/uim@latest add skeleton --platform swift
```

```bash title="Terminal"
npx @esuiss/uim@latest add skeleton --platform kotlin
```

### Manual

**Uniwind**

1. Install the dependencies:

```bash title="Terminal"
npx expo install cn react-native-reanimated react-native-worklets
```

2. Copy the source into `components/ui/skeleton.tsx`:

```tsx title="uniwind/components/ui/skeleton.tsx"
import { cn } from "cn"
import * as React from "react"
import type { View } from "react-native"
import Animated, {
  useAnimatedStyle,
  useSharedValue,
  withRepeat,
  withTiming,
} from "react-native-reanimated"

const duration = 1000

function Skeleton({
  className,
  ...props
}: React.ComponentProps<typeof View> & React.RefAttributes<View>) {
  const sv = useSharedValue(1)

  React.useEffect(() => {
    sv.value = withRepeat(withTiming(0.5, { duration }), -1, true)
  }, [sv])

  const style = useAnimatedStyle(() => ({
    opacity: sv.value,
  }))
  return (
    <Animated.View
      style={style}
      className={cn("rounded-md bg-surface-secondary", className)}
      {...props}
    />
  )
}

export { Skeleton }
```

3. Update the import paths to match your project.

**NativeWind**

1. Install the dependencies:

```bash title="Terminal"
npx expo install cn react-native-reanimated react-native-worklets
```

2. Copy the source into `components/ui/skeleton.tsx`:

```tsx title="nativewind/components/ui/skeleton.tsx"
import { cn } from "cn"
import * as React from "react"
import type { View } from "react-native"
import Animated, {
  useAnimatedStyle,
  useSharedValue,
  withRepeat,
  withTiming,
} from "react-native-reanimated"

const duration = 1000

function Skeleton({
  className,
  ...props
}: React.ComponentProps<typeof View> & React.RefAttributes<View>) {
  const sv = useSharedValue(1)

  React.useEffect(() => {
    sv.value = withRepeat(withTiming(0.5, { duration }), -1, true)
  }, [sv])

  const style = useAnimatedStyle(() => ({
    opacity: sv.value,
  }))
  return (
    <Animated.View
      style={style}
      className={cn("rounded-md bg-surface-secondary", className)}
      {...props}
    />
  )
}

export { Skeleton }
```

3. Update the import paths to match your project.

**StyleSheet**

1. Install the dependencies:

```bash title="Terminal"
npx expo install react-native-reanimated react-native-worklets
```

2. Copy the source into `components/ui/skeleton.tsx`:

```tsx title="stylesheet/components/ui/skeleton.tsx"
import * as React from "react"
import { StyleSheet, type View } from "react-native"
import Animated, {
  useAnimatedStyle,
  useSharedValue,
  withRepeat,
  withTiming,
} from "react-native-reanimated"
import { radius, useTheme } from "@/components/ui/theme"

const duration = 1000

const styles = StyleSheet.create({
  root: { borderRadius: radius.md },
})

function Skeleton({
  style,
  ...props
}: React.ComponentProps<typeof View> & React.RefAttributes<View>) {
  const { colors } = useTheme()
  const sv = useSharedValue(1)

  React.useEffect(() => {
    sv.value = withRepeat(withTiming(0.5, { duration }), -1, true)
  }, [sv])

  const animatedStyle = useAnimatedStyle(() => ({
    opacity: sv.value,
  }))
  return (
    <Animated.View
      style={[
        styles.root,
        { backgroundColor: colors.surfaceSecondary },
        style,
        animatedStyle,
      ]}
      {...props}
    />
  )
}

export { Skeleton }
```

3. Update the import paths to match your project.

**SwiftUI**

1. Target iOS 17 or later.

2. Copy the theme files every view uses:

```swift title="swift/Theme/Theme.swift"
import SwiftUI
import UIKit

struct RGBA: Sendable {
  let red: CGFloat
  let green: CGFloat
  let blue: CGFloat
  let alpha: CGFloat

  init(_ hex: UInt32, _ alpha: CGFloat = 1) {
    red = CGFloat((hex >> 16) & 0xFF) / 255
    green = CGFloat((hex >> 8) & 0xFF) / 255
    blue = CGFloat(hex & 0xFF) / 255
    self.alpha = alpha
  }

  var uiColor: UIColor {
    UIColor(red: red, green: green, blue: blue, alpha: alpha)
  }
}

extension Color {
  static func adaptive(light: RGBA, dark: RGBA) -> Color {
    let lightColor = light.uiColor
    let darkColor = dark.uiColor
    return Color(uiColor: UIColor { traits in
      traits.userInterfaceStyle == .dark ? darkColor : lightColor
    })
  }
}

public struct TextStyle: Sendable, Hashable {
  public let size: CGFloat
  public let lineHeight: CGFloat
  public let letterSpacing: CGFloat

  public init(size: CGFloat, lineHeight: CGFloat, letterSpacing: CGFloat) {
    self.size = size
    self.lineHeight = lineHeight
    self.letterSpacing = letterSpacing
  }

  public func font(weight: Font.Weight = .regular) -> Font {
    .system(size: size, weight: weight)
  }

  public var lineSpacing: CGFloat {
    max(0, lineHeight - UIFont.systemFont(ofSize: size).lineHeight)
  }
}

extension Hashable where Self == Font {
  public static func textStyle(_ style: TextStyle, weight: Font.Weight = .regular) -> Font {
    style.font(weight: weight)
  }
}

private struct TextStyleModifier: ViewModifier {
  let style: TextStyle
  let weight: Font.Weight

  func body(content: Content) -> some View {
    content
      .font(style.font(weight: weight))
      .tracking(style.letterSpacing)
      .lineSpacing(style.lineSpacing)
      .padding(.vertical, style.lineSpacing / 2)
  }
}

extension View {
  public func textStyle(_ style: TextStyle, weight: Font.Weight = .regular) -> some View {
    modifier(TextStyleModifier(style: style, weight: weight))
  }
}

public struct Shadow: Sendable, Hashable {
  public let color: Color
  public let radius: CGFloat
  public let x: CGFloat
  public let y: CGFloat

  public init(color: Color, radius: CGFloat, x: CGFloat = 0, y: CGFloat = 0) {
    self.color = color
    self.radius = radius
    self.x = x
    self.y = y
  }
}

extension View {
  public func shadow(_ shadow: Shadow) -> some View {
    self.shadow(color: shadow.color, radius: shadow.radius, x: shadow.x, y: shadow.y)
  }
}
```

```swift title="swift/Theme/Tokens.swift"
import SwiftUI

extension Color {
  public static let surface = Color.adaptive(light: .init(0xFFFFFF), dark: .init(0x000000))
  public static let surfaceSecondary = Color.adaptive(light: .init(0xF5F5F7), dark: .init(0x161617))
  public static let surfaceTertiary = Color.adaptive(light: .init(0xE8E8ED), dark: .init(0x2C2C2E))
  public static let surfaceRaised = Color.adaptive(light: .init(0xFFFFFF), dark: .init(0x1D1D1F))
  public static let label = Color.adaptive(light: .init(0x1D1D1F), dark: .init(0xF5F5F7))
  public static let labelSecondary = Color.adaptive(light: .init(0x6E6E73), dark: .init(0xA1A1A6))
  public static let labelTertiary = Color.adaptive(light: .init(0x86868B), dark: .init(0x86868B))
  public static let labelQuaternary = Color.adaptive(light: .init(0xD2D2D7), dark: .init(0x424245))
  public static let control = Color.adaptive(light: .init(0x000000, 0.04), dark: .init(0xFFFFFF, 0.1))
  public static let controlPressed = Color.adaptive(light: .init(0x000000, 0.12), dark: .init(0xFFFFFF, 0.22))
  public static let controlSelected = Color.adaptive(light: .init(0x1D1D1F), dark: .init(0xF5F5F7))
  public static let controlDisabled = Color.adaptive(light: .init(0x000000, 0.03), dark: .init(0xFFFFFF, 0.05))
  public static let onControlSelected = Color.adaptive(light: .init(0xFFFFFF), dark: .init(0x000000))
  public static let itemPressed = Color.adaptive(light: .init(0x000000, 0.08), dark: .init(0xFFFFFF, 0.12))
  public static let itemSelected = Color.adaptive(light: .init(0x000000, 0.06), dark: .init(0xFFFFFF, 0.1))
  public static let separator = Color.adaptive(light: .init(0xD2D2D7), dark: .init(0x424245))
  public static let separatorStrong = Color.adaptive(light: .init(0x86868B), dark: .init(0x6E6E73))
  public static let accent = Color.adaptive(light: .init(0x0071E3), dark: .init(0x0071E3))
  public static let accentPressed = Color.adaptive(light: .init(0x005BB8), dark: .init(0x004D9E))
  public static let accentSelected = Color.adaptive(light: .init(0x0071E3), dark: .init(0x0071E3))
  public static let accentDisabled = Color.adaptive(light: .init(0x0071E3, 0.4), dark: .init(0x0071E3, 0.4))
  public static let onAccent = Color.adaptive(light: .init(0xFFFFFF), dark: .init(0xFFFFFF))
  public static let accentSurface = Color.adaptive(light: .init(0x0071E3, 0.09), dark: .init(0x0071E3, 0.18))
  public static let accentSurfacePressed = Color.adaptive(light: .init(0x0071E3, 0.18), dark: .init(0x0071E3, 0.3))
  public static let link = Color.adaptive(light: .init(0x0066CC), dark: .init(0x2997FF))
  public static let focus = Color.adaptive(light: .init(0x0071E3), dark: .init(0x0071E3))
  public static let scrim = Color.adaptive(light: .init(0x000000, 0.48), dark: .init(0x000000, 0.48))
  public static let media = Color.adaptive(light: .init(0x000000), dark: .init(0x000000))
  public static let onMedia = Color.adaptive(light: .init(0xFFFFFF), dark: .init(0xFFFFFF))
  public static let danger = Color.adaptive(light: .init(0xD0000A), dark: .init(0xFF5447))
  public static let dangerSurface = Color.adaptive(light: .init(0xD70015, 0.08), dark: .init(0xFF453A, 0.2))
  public static let dangerSurfacePressed = Color.adaptive(light: .init(0xD70015, 0.16), dark: .init(0xFF453A, 0.36))
  public static let success = Color.adaptive(light: .init(0x008009), dark: .init(0x30D158))
  public static let successSurface = Color.adaptive(light: .init(0xEFFAF1), dark: .init(0x30D158, 0.16))
  public static let warning = Color.adaptive(light: .init(0xB64400), dark: .init(0xFF9F0A))
  public static let warningSurface = Color.adaptive(light: .init(0xFFF5EA), dark: .init(0xFF9F0A, 0.16))
}

public enum Radius {
  public static let xs: CGFloat = 3
  public static let sm: CGFloat = 5
  public static let md: CGFloat = 8
  public static let lg: CGFloat = 10
  public static let xl: CGFloat = 12
  public static let xl2: CGFloat = 18
  public static let xl3: CGFloat = 28
  public static let full: CGFloat = 9999
}

extension TextStyle {
  public static let xs3 = TextStyle(size: 11, lineHeight: 13, letterSpacing: 0.066)
  public static let xs2 = TextStyle(size: 12, lineHeight: 16, letterSpacing: 0)
  public static let xs = TextStyle(size: 13, lineHeight: 18, letterSpacing: -0.078)
  public static let sm = TextStyle(size: 15, lineHeight: 20, letterSpacing: -0.24)
  public static let md = TextStyle(size: 16, lineHeight: 21, letterSpacing: -0.32)
  public static let base = TextStyle(size: 17, lineHeight: 22, letterSpacing: -0.442)
  public static let lg = TextStyle(size: 20, lineHeight: 25, letterSpacing: -0.46)
  public static let xl = TextStyle(size: 22, lineHeight: 28, letterSpacing: -0.264)
  public static let xl2 = TextStyle(size: 28, lineHeight: 34, letterSpacing: 0.392)
  public static let xl3 = TextStyle(size: 34, lineHeight: 41, letterSpacing: 0.408)

  public static let allCases: [TextStyle] = [.xs3, .xs2, .xs, .sm, .md, .base, .lg, .xl, .xl2, .xl3]
}

extension Shadow {
  public static let md = Shadow(color: .black.opacity(0.08), radius: 6, x: 2, y: 4)
  public static let lg = Shadow(color: .black.opacity(0.12), radius: 12, y: 4)
}
```

3. Copy the source:

```swift title="swift/Components/Skeleton.swift"
import SwiftUI

public struct Skeleton: View {
  let cornerRadius: CGFloat

  @Environment(\.accessibilityReduceMotion) private var reduceMotion
  @State private var dimmed = false

  public init(cornerRadius: CGFloat = Radius.md) {
    self.cornerRadius = cornerRadius
  }

  public var body: some View {
    RoundedRectangle(cornerRadius: cornerRadius, style: .continuous)
      .fill(Color.surfaceSecondary)
      .opacity(dimmed ? 0.5 : 1)
      .onAppear {
        guard !reduceMotion else { return }
        withAnimation(.easeInOut(duration: 1).repeatForever(autoreverses: true)) {
          dimmed = true
        }
      }
      .onChange(of: reduceMotion) { _, reduced in
        if reduced {
          withAnimation(nil) { dimmed = false }
        }
      }
      .accessibilityHidden(true)
  }
}
```

4. Add the files to your app target.

**Jetpack Compose**

1. Set `minSdk` to 24 or higher and add the dependencies:

```kotlin title="build.gradle.kts"
implementation(platform("androidx.compose:compose-bom:2026.09.00"))
implementation("androidx.compose.foundation:foundation")
implementation("androidx.compose.ui:ui")
```

2. Copy the theme files every view uses:

```kt title="kotlin/theme/Theme.kt"
package com.esuiss.ui.theme

import androidx.compose.foundation.isSystemInDarkTheme
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.Immutable
import androidx.compose.runtime.staticCompositionLocalOf
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.dropShadow
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.Shape
import androidx.compose.ui.graphics.shadow.Shadow as DropShadow
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.text.style.LineHeightStyle
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.DpOffset
import androidx.compose.ui.unit.em
import androidx.compose.ui.unit.sp

internal fun textStyle(size: Double, lineHeight: Double, letterSpacing: Double) = TextStyle(
    fontSize = size.sp,
    lineHeight = lineHeight.sp,
    letterSpacing = letterSpacing.em,
    lineHeightStyle = LineHeightStyle(
        alignment = LineHeightStyle.Alignment.Center,
        trim = LineHeightStyle.Trim.None,
    ),
)

@Immutable
data class Shadow(
    val offsetX: Dp,
    val offsetY: Dp,
    val blur: Dp,
    val color: Color,
)

fun Modifier.shadow(shadow: Shadow, shape: Shape): Modifier = dropShadow(
    shape,
    DropShadow(
        radius = shadow.blur,
        color = shadow.color,
        offset = DpOffset(shadow.offsetX, shadow.offsetY),
    ),
)

val LocalColors = staticCompositionLocalOf { LightColors }

object EsuissTheme {
    val colors: Colors
        @Composable get() = LocalColors.current

    val typography: Typography
        get() = Typography

    val radius: Radius
        get() = Radius

    val shadows: Shadows
        get() = Shadows
}

@Composable
fun EsuissTheme(
    darkTheme: Boolean = isSystemInDarkTheme(),
    content: @Composable () -> Unit,
) {
    CompositionLocalProvider(
        LocalColors provides if (darkTheme) DarkColors else LightColors,
        content = content,
    )
}
```

```kt title="kotlin/theme/Tokens.kt"
package com.esuiss.ui.theme

import androidx.compose.runtime.Immutable
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

@Immutable
data class Colors(
    val surface: Color,
    val surfaceSecondary: Color,
    val surfaceTertiary: Color,
    val surfaceRaised: Color,
    val label: Color,
    val labelSecondary: Color,
    val labelTertiary: Color,
    val labelQuaternary: Color,
    val control: Color,
    val controlPressed: Color,
    val controlSelected: Color,
    val controlDisabled: Color,
    val onControlSelected: Color,
    val itemPressed: Color,
    val itemSelected: Color,
    val separator: Color,
    val separatorStrong: Color,
    val accent: Color,
    val accentPressed: Color,
    val accentSelected: Color,
    val accentDisabled: Color,
    val onAccent: Color,
    val accentSurface: Color,
    val accentSurfacePressed: Color,
    val link: Color,
    val focus: Color,
    val scrim: Color,
    val media: Color,
    val onMedia: Color,
    val danger: Color,
    val dangerSurface: Color,
    val dangerSurfacePressed: Color,
    val success: Color,
    val successSurface: Color,
    val warning: Color,
    val warningSurface: Color,
    val blue: Color,
    val green: Color,
    val orange: Color,
    val red: Color,
    val yellow: Color,
    val purple: Color,
    val pink: Color,
    val indigo: Color,
    val teal: Color,
    val mint: Color,
    val cyan: Color,
    val brown: Color,
    val gray: Color,
    val isDark: Boolean,
)

val LightColors = Colors(
    surface = Color(0xFFFFFFFF),
    surfaceSecondary = Color(0xFFF5F5F7),
    surfaceTertiary = Color(0xFFE8E8ED),
    surfaceRaised = Color(0xFFFFFFFF),
    label = Color(0xFF1D1D1F),
    labelSecondary = Color(0xFF6E6E73),
    labelTertiary = Color(0xFF86868B),
    labelQuaternary = Color(0xFFD2D2D7),
    control = Color(0xFF000000).copy(alpha = 0.04f),
    controlPressed = Color(0xFF000000).copy(alpha = 0.12f),
    controlSelected = Color(0xFF1D1D1F),
    controlDisabled = Color(0xFF000000).copy(alpha = 0.03f),
    onControlSelected = Color(0xFFFFFFFF),
    itemPressed = Color(0xFF000000).copy(alpha = 0.08f),
    itemSelected = Color(0xFF000000).copy(alpha = 0.06f),
    separator = Color(0xFFD2D2D7),
    separatorStrong = Color(0xFF86868B),
    accent = Color(0xFF0071E3),
    accentPressed = Color(0xFF005BB8),
    accentSelected = Color(0xFF0071E3),
    accentDisabled = Color(0xFF0071E3).copy(alpha = 0.4f),
    onAccent = Color(0xFFFFFFFF),
    accentSurface = Color(0xFF0071E3).copy(alpha = 0.09f),
    accentSurfacePressed = Color(0xFF0071E3).copy(alpha = 0.18f),
    link = Color(0xFF0066CC),
    focus = Color(0xFF0071E3),
    scrim = Color(0xFF000000).copy(alpha = 0.48f),
    media = Color(0xFF000000),
    onMedia = Color(0xFFFFFFFF),
    danger = Color(0xFFD0000A),
    dangerSurface = Color(0xFFD70015).copy(alpha = 0.08f),
    dangerSurfacePressed = Color(0xFFD70015).copy(alpha = 0.16f),
    success = Color(0xFF008009),
    successSurface = Color(0xFFEFFAF1),
    warning = Color(0xFFB64400),
    warningSurface = Color(0xFFFFF5EA),
    blue = Color(0xFF007AFF),
    green = Color(0xFF34C759),
    orange = Color(0xFFFF9500),
    red = Color(0xFFFF3B30),
    yellow = Color(0xFFFFCC00),
    purple = Color(0xFFAF52DE),
    pink = Color(0xFFFF2D55),
    indigo = Color(0xFF5856D6),
    teal = Color(0xFF30B0C7),
    mint = Color(0xFF00C7BE),
    cyan = Color(0xFF32ADE6),
    brown = Color(0xFFA2845E),
    gray = Color(0xFF8E8E93),
    isDark = false,
)

val DarkColors = Colors(
    surface = Color(0xFF000000),
    surfaceSecondary = Color(0xFF161617),
    surfaceTertiary = Color(0xFF2C2C2E),
    surfaceRaised = Color(0xFF1D1D1F),
    label = Color(0xFFF5F5F7),
    labelSecondary = Color(0xFFA1A1A6),
    labelTertiary = Color(0xFF86868B),
    labelQuaternary = Color(0xFF424245),
    control = Color(0xFFFFFFFF).copy(alpha = 0.1f),
    controlPressed = Color(0xFFFFFFFF).copy(alpha = 0.22f),
    controlSelected = Color(0xFFF5F5F7),
    controlDisabled = Color(0xFFFFFFFF).copy(alpha = 0.05f),
    onControlSelected = Color(0xFF000000),
    itemPressed = Color(0xFFFFFFFF).copy(alpha = 0.12f),
    itemSelected = Color(0xFFFFFFFF).copy(alpha = 0.1f),
    separator = Color(0xFF424245),
    separatorStrong = Color(0xFF6E6E73),
    accent = Color(0xFF0071E3),
    accentPressed = Color(0xFF004D9E),
    accentSelected = Color(0xFF0071E3),
    accentDisabled = Color(0xFF0071E3).copy(alpha = 0.4f),
    onAccent = Color(0xFFFFFFFF),
    accentSurface = Color(0xFF0071E3).copy(alpha = 0.18f),
    accentSurfacePressed = Color(0xFF0071E3).copy(alpha = 0.3f),
    link = Color(0xFF2997FF),
    focus = Color(0xFF0071E3),
    scrim = Color(0xFF000000).copy(alpha = 0.48f),
    media = Color(0xFF000000),
    onMedia = Color(0xFFFFFFFF),
    danger = Color(0xFFFF5447),
    dangerSurface = Color(0xFFFF453A).copy(alpha = 0.2f),
    dangerSurfacePressed = Color(0xFFFF453A).copy(alpha = 0.36f),
    success = Color(0xFF30D158),
    successSurface = Color(0xFF30D158).copy(alpha = 0.16f),
    warning = Color(0xFFFF9F0A),
    warningSurface = Color(0xFFFF9F0A).copy(alpha = 0.16f),
    blue = Color(0xFF0A84FF),
    green = Color(0xFF30D158),
    orange = Color(0xFFFF9F0A),
    red = Color(0xFFFF453A),
    yellow = Color(0xFFFFD60A),
    purple = Color(0xFFBF5AF2),
    pink = Color(0xFFFF375F),
    indigo = Color(0xFF5E5CE6),
    teal = Color(0xFF40C8E0),
    mint = Color(0xFF66D4CF),
    cyan = Color(0xFF64D2FF),
    brown = Color(0xFFAC8E68),
    gray = Color(0xFF8E8E93),
    isDark = true,
)

object Radius {
    val xs = 3.dp
    val sm = 5.dp
    val md = 8.dp
    val lg = 10.dp
    val xl = 12.dp
    val xl2 = 18.dp
    val xl3 = 28.dp
    val full = 9999.dp
}

object Typography {
    val xs3 = textStyle(11.0, 13.0, 0.006)
    val xs2 = textStyle(12.0, 16.0, 0.0)
    val xs = textStyle(13.0, 18.0, -0.006)
    val sm = textStyle(15.0, 20.0, -0.016)
    val md = textStyle(16.0, 21.0, -0.02)
    val base = textStyle(17.0, 22.0, -0.026)
    val lg = textStyle(20.0, 25.0, -0.023)
    val xl = textStyle(22.0, 28.0, -0.012)
    val xl2 = textStyle(28.0, 34.0, 0.014)
    val xl3 = textStyle(34.0, 41.0, 0.012)

    val all = listOf(xs3, xs2, xs, sm, md, base, lg, xl, xl2, xl3)
}

object Shadows {
    val md = Shadow(2.dp, 4.dp, 12.dp, Color.Black.copy(alpha = 0.08f))
    val lg = Shadow(0.dp, 4.dp, 24.dp, Color.Black.copy(alpha = 0.12f))
}
```

3. Copy the source and every file it uses:

```kt title="kotlin/components/Skeleton.kt"
package com.esuiss.ui.components

import androidx.compose.animation.core.LinearEasing
import androidx.compose.animation.core.RepeatMode
import androidx.compose.animation.core.animateFloat
import androidx.compose.animation.core.infiniteRepeatable
import androidx.compose.animation.core.rememberInfiniteTransition
import androidx.compose.animation.core.tween
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Shape
import androidx.compose.ui.graphics.graphicsLayer
import androidx.compose.ui.semantics.clearAndSetSemantics
import com.esuiss.ui.theme.EsuissTheme
import com.esuiss.ui.theme.Radius

@Composable
fun Skeleton(
    modifier: Modifier = Modifier,
    shape: Shape = RoundedCornerShape(Radius.md),
) {
    val reduced = formReducedMotion()
    val transition = rememberInfiniteTransition(label = "skeleton")
    val pulse by transition.animateFloat(
        initialValue = 1f,
        targetValue = 0.5f,
        animationSpec = infiniteRepeatable(tween(1000, easing = LinearEasing), RepeatMode.Reverse),
        label = "skeleton",
    )
    Box(
        modifier
            .clearAndSetSemantics {}
            .graphicsLayer { alpha = if (reduced) 1f else pulse }
            .background(EsuissTheme.colors.surfaceSecondary, shape),
    )
}
```

```kt title="kotlin/components/FormSupport.kt"
package com.esuiss.ui.components

import android.provider.Settings
import androidx.compose.animation.core.CubicBezierEasing
import androidx.compose.foundation.background
import androidx.compose.foundation.border
import androidx.compose.foundation.gestures.Orientation
import androidx.compose.foundation.text.selection.TextSelectionColors
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.draw.drawWithContent
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.geometry.Size
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.Shape
import androidx.compose.ui.layout.Layout
import androidx.compose.ui.layout.layout
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.unit.Constraints
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.LayoutDirection
import androidx.compose.ui.unit.constrainHeight
import androidx.compose.ui.unit.constrainWidth
import androidx.compose.ui.unit.dp
import com.esuiss.ui.theme.Colors
import com.esuiss.ui.theme.Shadow

internal val FormShadowXs = Shadow(0.dp, 1.dp, 2.dp, Color.Black.copy(alpha = 0.05f))

internal val FormShadowSm = Shadow(0.dp, 1.dp, 3.dp, Color.Black.copy(alpha = 0.1f))

internal val FormEasing = CubicBezierEasing(0.32f, 0.72f, 0f, 1f)

internal fun Modifier.formTouchTarget(): Modifier = layout { measurable, constraints ->
    val minimum = 48.dp.roundToPx()
    val placeable = measurable.measure(constraints)
    val width = constraints.constrainWidth(maxOf(placeable.width, minimum))
    val height = constraints.constrainHeight(maxOf(placeable.height, minimum))
    layout(width, height) {
        placeable.place((width - placeable.width) / 2, (height - placeable.height) / 2)
    }
}

@Composable
internal fun formReducedMotion(): Boolean {
    val context = LocalContext.current
    return remember(context) {
        Settings.Global.getFloat(context.contentResolver, Settings.Global.ANIMATOR_DURATION_SCALE, 1f) == 0f
    }
}

internal fun formSelectionColors(colors: Colors) = TextSelectionColors(
    handleColor = colors.accent,
    backgroundColor = colors.accent.copy(alpha = 0.3f),
)

internal fun Modifier.formInputSurface(
    colors: Colors,
    shape: Shape,
    focused: Boolean,
    invalid: Boolean,
    enabled: Boolean,
): Modifier {
    val background = when {
        !enabled -> colors.controlDisabled
        invalid -> colors.danger.copy(alpha = if (colors.isDark) 0.1f else 0.05f)
        else -> colors.control
    }
    val border = when {
        invalid -> colors.danger
        focused -> colors.focus
        else -> Color.Transparent
    }
    return clip(shape).background(background, shape).border(1.dp, border, shape)
}

@Composable
internal fun FormDividedStack(
    orientation: Orientation,
    dividerColor: Color,
    modifier: Modifier = Modifier,
    dividerInsetStart: Dp = 0.dp,
    content: @Composable () -> Unit,
) {
    val boundaries = remember { mutableStateOf(IntArray(0)) }
    val vertical = orientation == Orientation.Vertical
    Layout(
        content = content,
        modifier = modifier.drawWithContent {
            drawContent()
            val stroke = 1.dp.toPx()
            val inset = dividerInsetStart.toPx()
            boundaries.value.forEach { position ->
                if (vertical) {
                    val start = if (layoutDirection == LayoutDirection.Rtl) 0f else inset
                    drawRect(dividerColor, Offset(start, position.toFloat()), Size(size.width - inset, stroke))
                } else {
                    val x = if (layoutDirection == LayoutDirection.Rtl) size.width - position - stroke else position.toFloat()
                    drawRect(dividerColor, Offset(x, 0f), Size(stroke, size.height))
                }
            }
        },
    ) { measurables, constraints ->
        if (vertical) {
            val width = if (constraints.hasFixedWidth) {
                constraints.maxWidth
            } else {
                constraints.constrainWidth(measurables.maxOfOrNull { it.maxIntrinsicWidth(Constraints.Infinity) } ?: 0)
            }
            val placeables = measurables.map {
                it.measure(Constraints(minWidth = width, maxWidth = width))
            }
            val offsets = IntArray(placeables.size)
            var y = 0
            placeables.forEachIndexed { index, placeable ->
                offsets[index] = y
                y += placeable.height
            }
            val next = offsets.drop(1).toIntArray()
            if (!next.contentEquals(boundaries.value)) boundaries.value = next
            layout(width, constraints.constrainHeight(y)) {
                placeables.forEachIndexed { index, placeable -> placeable.placeRelative(0, offsets[index]) }
            }
        } else {
            val height = if (constraints.hasFixedHeight) {
                constraints.maxHeight
            } else {
                constraints.constrainHeight(measurables.maxOfOrNull { it.maxIntrinsicHeight(Constraints.Infinity) } ?: 0)
            }
            val placeables = measurables.map {
                it.measure(Constraints(minHeight = height, maxHeight = height))
            }
            val offsets = IntArray(placeables.size)
            var x = 0
            placeables.forEachIndexed { index, placeable ->
                offsets[index] = x
                x += placeable.width
            }
            val next = offsets.drop(1).toIntArray()
            if (!next.contentEquals(boundaries.value)) boundaries.value = next
            layout(constraints.constrainWidth(x), height) {
                placeables.forEachIndexed { index, placeable -> placeable.placeRelative(offsets[index], 0) }
            }
        }
    }
}
```

4. Update the `com.esuiss.ui` package names to match your project.

## Usage

```tsx
import { Skeleton } from "@/components/ui/skeleton"
```

```tsx
<Skeleton className="h-4 w-48" />
```

Set width, height and radius through `className`, for example `h-4 w-48` for a line of text or `size-12 rounded-full` for an avatar. Compose several skeletons to mirror the layout of the loaded content, then swap them for the real content once it arrives.

## Examples

### Profile

An avatar circle with two lines of text.

![Preview](https://uim.suiss.app/previews/components-skeleton--profile.light.webp)

```tsx
import { View } from "react-native"
import { Skeleton } from "@/components/ui/skeleton"

export function SkeletonProfileExample() {
  return (
    <View className="flex-row items-center gap-4">
      <Skeleton className="size-12 rounded-full" />
      <View className="gap-2">
        <Skeleton className="h-4 w-48" />
        <Skeleton className="h-4 w-36" />
      </View>
    </View>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct SkeletonProfileExample: View {
  var body: some View {
    HStack(spacing: 16) {
      Skeleton(cornerRadius: Radius.full)
        .frame(width: 48, height: 48)
      VStack(alignment: .leading, spacing: 8) {
        Skeleton().frame(width: 192, height: 16)
        Skeleton().frame(width: 144, height: 16)
      }
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.shape.CircleShape
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Skeleton

@Composable
fun SkeletonProfile() {
    Row(horizontalArrangement = Arrangement.spacedBy(16.dp), verticalAlignment = Alignment.CenterVertically) {
        Skeleton(Modifier.size(48.dp), shape = CircleShape)
        Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
            Skeleton(Modifier.width(192.dp).height(16.dp))
            Skeleton(Modifier.width(144.dp).height(16.dp))
        }
    }
}
```

### Card

A media block with two lines of text below it.

![Preview](https://uim.suiss.app/previews/components-skeleton--card.light.webp)

```tsx
import { View } from "react-native"
import { Skeleton } from "@/components/ui/skeleton"

export function SkeletonCardExample() {
  return (
    <View className="gap-3">
      <Skeleton className="h-32 w-full rounded-xl" />
      <View className="gap-2">
        <Skeleton className="h-4 w-3/4" />
        <Skeleton className="h-4 w-1/2" />
      </View>
    </View>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct SkeletonCardExample: View {
  var body: some View {
    VStack(alignment: .leading, spacing: 12) {
      Skeleton(cornerRadius: Radius.xl)
        .frame(height: 128)
        .frame(maxWidth: .infinity)
      GeometryReader { proxy in
        VStack(alignment: .leading, spacing: 8) {
          Skeleton().frame(width: proxy.size.width * 0.75, height: 16)
          Skeleton().frame(width: proxy.size.width * 0.5, height: 16)
        }
      }
      .frame(height: 40)
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Skeleton
import com.esuiss.ui.theme.Radius

@Composable
fun SkeletonCard() {
    Column(Modifier.fillMaxWidth(), verticalArrangement = Arrangement.spacedBy(12.dp)) {
        Skeleton(Modifier.fillMaxWidth().height(128.dp), shape = RoundedCornerShape(Radius.xl))
        Column(Modifier.fillMaxWidth(), verticalArrangement = Arrangement.spacedBy(8.dp)) {
            Skeleton(Modifier.fillMaxWidth(0.75f).height(16.dp))
            Skeleton(Modifier.fillMaxWidth(0.5f).height(16.dp))
        }
    }
}
```

### List

Rows with a thumbnail and two lines of text.

![Preview](https://uim.suiss.app/previews/components-skeleton--list.light.webp)

```tsx
import { View } from "react-native"
import { Skeleton } from "@/components/ui/skeleton"

export function SkeletonListExample() {
  return (
    <View className="gap-4">
      {["one", "two", "three", "four"].map((key) => (
        <View key={key} className="flex-row items-center gap-3">
          <Skeleton className="size-10 rounded-md" />
          <View className="flex-1 gap-2">
            <Skeleton className="h-4 w-2/3" />
            <Skeleton className="h-3 w-1/3" />
          </View>
        </View>
      ))}
    </View>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct SkeletonListExample: View {
  var body: some View {
    VStack(alignment: .leading, spacing: 16) {
      ForEach(["one", "two", "three", "four"], id: \.self) { _ in
        HStack(spacing: 12) {
          Skeleton(cornerRadius: Radius.md)
            .frame(width: 40, height: 40)
          GeometryReader { proxy in
            VStack(alignment: .leading, spacing: 8) {
              Skeleton().frame(width: proxy.size.width * 2 / 3, height: 16)
              Skeleton().frame(width: proxy.size.width / 3, height: 12)
            }
            .frame(maxHeight: .infinity)
          }
          .frame(height: 40)
        }
      }
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Skeleton
import com.esuiss.ui.theme.Radius

@Composable
fun SkeletonList() {
    Column(Modifier.fillMaxWidth(), verticalArrangement = Arrangement.spacedBy(16.dp)) {
        repeat(4) {
            Row(horizontalArrangement = Arrangement.spacedBy(12.dp), verticalAlignment = Alignment.CenterVertically) {
                Skeleton(Modifier.size(40.dp), shape = RoundedCornerShape(Radius.md))
                Column(Modifier.weight(1f), verticalArrangement = Arrangement.spacedBy(8.dp)) {
                    Skeleton(Modifier.fillMaxWidth(2f / 3f).height(16.dp))
                    Skeleton(Modifier.fillMaxWidth(1f / 3f).height(12.dp))
                }
            }
        }
    }
}
```

## API Reference

### Skeleton

## Accessibility

- The skeleton is a plain view with no role or label. If loading state matters to the user, announce it elsewhere, for example with a `Spinner` that has an `accessibilityLabel`.

## Notes

- Uses the `bg-surface-secondary` token.
- The pulse runs on the UI thread through Reanimated, with a 1000 ms cycle.
- Light and dark colors follow the system appearance.