# Bottom Bar

A bar pinned to the bottom of a screen for primary actions, which rises above the keyboard.

Bottom Bar 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/bottom-bar

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

```tsx
import { View } from "react-native"
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
import { Button } from "@/components/ui/button"
import { Text } from "@/components/ui/text"

function Page({ children }: { children: React.ReactNode }) {
  return (
    <View className="-m-4 flex-1">
      <View className="flex-1 gap-2 p-4">
        <Text variant="h3">Review order</Text>
        <Text variant="muted">2 items, delivery on Thursday.</Text>
      </View>
      {children}
    </View>
  )
}

export function BottomBarExample() {
  return (
    <Page>
      <BottomBar>
        <BottomBarContent>
          <Button size="lg" block>
            <Text>Continue</Text>
          </Button>
        </BottomBarContent>
      </BottomBar>
    </Page>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct BottomBarExample: View {
  var body: some View {
    BottomBarPage {
      BottomBar(separator: false) {
        BottomBarContent {
          Button("Continue") {}.buttonStyle(.variant(size: .lg, block: true))
        }
      }
    }
  }
}

struct BottomBarPage<Bar: View>: View {
  @ViewBuilder let bar: () -> Bar

  var body: some View {
    VStack(spacing: 0) {
      VStack(alignment: .leading, spacing: 8) {
        Text("Review order").textVariant(.h3)
        Text("2 items, delivery on Thursday.").textVariant(.muted)
      }
      .padding(16)
      .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
      bar()
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.BottomBar
import com.esuiss.ui.components.BottomBarContent
import com.esuiss.ui.components.Button
import com.esuiss.ui.components.ButtonSize
import com.esuiss.ui.components.Screen
import com.esuiss.ui.components.ScreenEdge
import com.esuiss.ui.components.Text
import com.esuiss.ui.components.TextVariant

@Composable
fun BottomBarPage(page: @Composable ColumnScope.() -> Unit, bar: @Composable () -> Unit) {
    Screen(edges = setOf(ScreenEdge.Top, ScreenEdge.Left, ScreenEdge.Right)) {
        Column(Modifier.fillMaxSize()) {
            Column(
                Modifier.weight(1f).fillMaxWidth().padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
                content = page,
            )
            bar()
        }
    }
}

@Composable
fun BottomBarOrder(bar: @Composable () -> Unit) {
    BottomBarPage(
        page = {
            Text("Review order", variant = TextVariant.H3)
            Text("2 items, delivery on Thursday.", variant = TextVariant.Muted)
        },
        bar = bar,
    )
}

@Composable
fun BottomBarDefault() {
    BottomBarOrder {
        BottomBar {
            BottomBarContent {
                Button("Continue", onClick = {}, size = ButtonSize.Lg, block = true)
            }
        }
    }
}
```

`BottomBar` is an animated `View` that adds bottom padding equal to the safe-area inset, or to the keyboard height while the keyboard is open, and animates between them with the keyboard's own timing. `BottomBarContent` adds the standard padding and spacing for the buttons inside.

Use it for the main call to action of a screen, such as checkout or a form submit button.

## Installation

```bash title="Terminal"
npx @esuiss/uim@latest add bottom-bar
```

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

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

The CLI also adds what it builds on: [Screen](/docs/components/screen).

### Manual

**Uniwind**

1. Install the dependencies:

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

2. Add the pieces it builds on: [Screen](/docs/components/screen), and the primitives `components/primitives/keyboard.tsx`.

3. Copy the source into `components/ui/bottom-bar.tsx`:

```tsx title="uniwind/components/ui/bottom-bar.tsx"
import { cn } from "cn"
import * as React from "react"
import { View, type ViewProps } from "react-native"
import {
  Easing,
  ReduceMotion,
  useAnimatedStyle,
  useSharedValue,
  withTiming,
} from "react-native-reanimated"
import { useSafeAreaInsets } from "react-native-safe-area-context"
import { useKeyboard } from "@/components/primitives/keyboard"
import { AnimatedView } from "@/components/ui/animated-view"
import { ScreenContext } from "@/components/ui/screen"

const EASING = Easing.bezier(0.17, 0.59, 0.4, 0.77)

function BottomBar({
  separator = false,
  className,
  style,
  ...props
}: ViewProps & {
  separator?: boolean
}) {
  const insets = useSafeAreaInsets()
  const screen = React.useContext(ScreenContext)
  const keyboard = useKeyboard()
  const consumed = screen?.edges.includes("bottom") ? insets.bottom : 0
  const target = Math.max(
    0,
    (keyboard.height > 0 ? keyboard.height : insets.bottom) - consumed
  )
  const padding = useSharedValue(target)

  React.useEffect(() => {
    padding.value = withTiming(target, {
      duration: keyboard.duration,
      easing: EASING,
      reduceMotion: ReduceMotion.System,
    })
  }, [target, keyboard.duration, padding])

  const animatedStyle = useAnimatedStyle(() => ({
    paddingBottom: padding.value,
  }))

  return (
    <AnimatedView
      className={cn(
        "bg-surface",
        separator && "border-t border-separator",
        className
      )}
      style={[animatedStyle, style]}
      {...props}
    />
  )
}

function BottomBarContent({ className, ...props }: ViewProps) {
  return <View className={cn("gap-2 px-4 py-3", className)} {...props} />
}

export { BottomBar, BottomBarContent }
```

4. 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-safe-area-context react-native-worklets
```

2. Add the pieces it builds on: [Screen](/docs/components/screen), and the primitives `components/primitives/keyboard.tsx`.

3. Copy the source into `components/ui/bottom-bar.tsx`:

```tsx title="nativewind/components/ui/bottom-bar.tsx"
import { cn } from "cn"
import * as React from "react"
import { View, type ViewProps } from "react-native"
import {
  Easing,
  ReduceMotion,
  useAnimatedStyle,
  useSharedValue,
  withTiming,
} from "react-native-reanimated"
import { useSafeAreaInsets } from "react-native-safe-area-context"
import { useKeyboard } from "@/components/primitives/keyboard"
import { AnimatedView } from "@/components/ui/animated-view"
import { ScreenContext } from "@/components/ui/screen"

const EASING = Easing.bezier(0.17, 0.59, 0.4, 0.77)

function BottomBar({
  separator = false,
  className,
  style,
  ...props
}: ViewProps & {
  separator?: boolean
}) {
  const insets = useSafeAreaInsets()
  const screen = React.useContext(ScreenContext)
  const keyboard = useKeyboard()
  const consumed = screen?.edges.includes("bottom") ? insets.bottom : 0
  const target = Math.max(
    0,
    (keyboard.height > 0 ? keyboard.height : insets.bottom) - consumed
  )
  const padding = useSharedValue(target)

  React.useEffect(() => {
    padding.value = withTiming(target, {
      duration: keyboard.duration,
      easing: EASING,
      reduceMotion: ReduceMotion.System,
    })
  }, [target, keyboard.duration, padding])

  const animatedStyle = useAnimatedStyle(() => ({
    paddingBottom: padding.value,
  }))

  return (
    <AnimatedView
      className={cn(
        "bg-surface",
        separator && "border-t border-separator",
        className
      )}
      style={[animatedStyle, style]}
      {...props}
    />
  )
}

function BottomBarContent({ className, ...props }: ViewProps) {
  return <View className={cn("gap-2 px-4 py-3", className)} {...props} />
}

export { BottomBar, BottomBarContent }
```

4. Update the import paths to match your project.

**StyleSheet**

1. Install the dependencies:

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

2. Add the pieces it builds on: [Screen](/docs/components/screen), and the primitives `components/primitives/keyboard.tsx`.

3. Copy the source into `components/ui/bottom-bar.tsx`:

```tsx title="stylesheet/components/ui/bottom-bar.tsx"
import * as React from "react"
import { StyleSheet, View, type ViewProps } from "react-native"
import {
  Easing,
  ReduceMotion,
  useAnimatedStyle,
  useSharedValue,
  withTiming,
} from "react-native-reanimated"
import { useSafeAreaInsets } from "react-native-safe-area-context"
import { useKeyboard } from "@/components/primitives/keyboard"
import { AnimatedView } from "@/components/ui/animated-view"
import { ScreenContext } from "@/components/ui/screen"
import { useTheme } from "@/components/ui/theme"

const EASING = Easing.bezier(0.17, 0.59, 0.4, 0.77)

const styles = StyleSheet.create({
  separator: { borderTopWidth: 1 },
  content: { gap: 8, paddingHorizontal: 16, paddingVertical: 12 },
})

function BottomBar({
  separator = false,
  style,
  ...props
}: ViewProps & {
  separator?: boolean
}) {
  const { colors } = useTheme()
  const insets = useSafeAreaInsets()
  const screen = React.useContext(ScreenContext)
  const keyboard = useKeyboard()
  const consumed = screen?.edges.includes("bottom") ? insets.bottom : 0
  const target = Math.max(
    0,
    (keyboard.height > 0 ? keyboard.height : insets.bottom) - consumed
  )
  const padding = useSharedValue(target)

  React.useEffect(() => {
    padding.value = withTiming(target, {
      duration: keyboard.duration,
      easing: EASING,
      reduceMotion: ReduceMotion.System,
    })
  }, [target, keyboard.duration, padding])

  const animatedStyle = useAnimatedStyle(() => ({
    paddingBottom: padding.value,
  }))

  return (
    <AnimatedView
      style={[
        { backgroundColor: colors.surface },
        separator && [styles.separator, { borderColor: colors.separator }],
        animatedStyle,
        style,
      ]}
      {...props}
    />
  )
}

function BottomBarContent({ style, ...props }: ViewProps) {
  return <View style={[styles.content, style]} {...props} />
}

export { BottomBar, BottomBarContent }
```

4. 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 and every file it uses:

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

public struct BottomBar<Content: View>: View {
  let separator: Bool
  let content: Content

  @Environment(\.screenBackground) private var background

  public init(separator: Bool = true, @ViewBuilder content: () -> Content) {
    self.separator = separator
    self.content = content()
  }

  public var body: some View {
    VStack(spacing: 0) {
      content
    }
    .frame(maxWidth: .infinity)
    .background(background.ignoresSafeArea(.container, edges: .bottom))
    .overlay(alignment: .top) {
      if separator {
        Color.separator.frame(height: 1)
      }
    }
    .accessibilityElement(children: .contain)
  }
}

public struct BottomBarContent<Content: View>: View {
  let content: Content

  public init(@ViewBuilder content: () -> Content) {
    self.content = content()
  }

  public var body: some View {
    VStack(spacing: 8) {
      content
    }
    .padding(.horizontal, 16)
    .padding(.vertical, 12)
    .frame(maxWidth: .infinity)
  }
}
```

```swift title="swift/Components/KeyboardScrollView.swift"
import SwiftUI
import UIKit

public struct KeyboardScrollView<Content: View>: View {
  let showsIndicators: Bool
  let content: Content

  public init(showsIndicators: Bool = true, @ViewBuilder content: () -> Content) {
    self.showsIndicators = showsIndicators
    self.content = content()
  }

  public var body: some View {
    ScrollView(.vertical, showsIndicators: showsIndicators) {
      content
        .frame(maxWidth: .infinity, alignment: .topLeading)
        .background {
          Color.clear
            .contentShape(Rectangle())
            .onTapGesture { KeyboardScrollView.dismissKeyboard() }
        }
    }
    .scrollDismissesKeyboard(.interactively)
  }

  @MainActor
  static func dismissKeyboard() {
    UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
  }
}
```

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

extension EnvironmentValues {
  @Entry var screenBackground: Color = .surface
}

public struct Screen<Content: View>: View {
  public enum Background: CaseIterable, Sendable {
    case surface, surfaceSecondary

    var color: Color {
      switch self {
      case .surface: .surface
      case .surfaceSecondary: .surfaceSecondary
      }
    }
  }

  let edges: Edge.Set
  let background: Background
  let content: Content

  public init(
    edges: Edge.Set = .all,
    background: Background = .surface,
    @ViewBuilder content: () -> Content
  ) {
    self.edges = edges
    self.background = background
    self.content = content()
  }

  public var body: some View {
    VStack(spacing: 0) {
      content
    }
    .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
    .ignoresSafeArea(.container, edges: Edge.Set.all.subtracting(edges))
    .foregroundStyle(Color.label)
    .background(background.color.ignoresSafeArea())
    .environment(\.screenBackground, background.color)
  }
}

public struct ScreenContent<Content: View>: View {
  let scroll: Bool
  let padded: Bool
  let content: Content

  public init(scroll: Bool = true, padded: Bool = true, @ViewBuilder content: () -> Content) {
    self.scroll = scroll
    self.padded = padded
    self.content = content()
  }

  public var body: some View {
    if scroll {
      KeyboardScrollView {
        stack
      }
    } else {
      stack
        .frame(maxHeight: .infinity, alignment: .top)
    }
  }

  private var stack: some View {
    VStack(alignment: .leading, spacing: 16) {
      content
    }
    .padding(padded ? 16 : 0)
    .frame(maxWidth: .infinity, alignment: .leading)
  }
}
```

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/BottomBar.kt"
package com.esuiss.ui.components

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.WindowInsets
import androidx.compose.foundation.layout.WindowInsetsSides
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.only
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.safeDrawing
import androidx.compose.foundation.layout.windowInsetsPadding
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.drawBehind
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.geometry.Size
import androidx.compose.ui.platform.LocalDensity
import androidx.compose.ui.unit.dp
import com.esuiss.ui.theme.EsuissTheme

@Composable
fun BottomBar(
    modifier: Modifier = Modifier,
    separator: Boolean = false,
    content: @Composable ColumnScope.() -> Unit,
) {
    val colors = EsuissTheme.colors
    Column(
        modifier = modifier
            .fillMaxWidth()
            .background(colors.surface)
            .then(
                if (separator) {
                    Modifier.drawBehind { drawRect(colors.separator, Offset.Zero, Size(size.width, 1.dp.toPx())) }
                } else {
                    Modifier
                },
            )
            .windowInsetsPadding(WindowInsets.safeDrawing.only(WindowInsetsSides.Bottom + WindowInsetsSides.Horizontal))
            .padding(bottom = with(LocalDensity.current) { (LocalKeyboardAccessory.current?.height ?: 0).toDp() }),
        content = content,
    )
}

@Composable
fun BottomBarContent(
    modifier: Modifier = Modifier,
    horizontalAlignment: Alignment.Horizontal = Alignment.CenterHorizontally,
    content: @Composable ColumnScope.() -> Unit,
) {
    Column(
        modifier = modifier
            .fillMaxWidth()
            .padding(horizontal = 16.dp, vertical = 12.dp),
        verticalArrangement = Arrangement.spacedBy(8.dp),
        horizontalAlignment = horizontalAlignment,
        content = content,
    )
}
```

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

import androidx.compose.runtime.compositionLocalOf
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.dp

val LocalContentStyle = compositionLocalOf { TextStyle.Default }

val LocalContentColor = compositionLocalOf { Color.Unspecified }

val LocalIconSize = compositionLocalOf { 20.dp }
```

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

import android.app.Activity
import android.content.Context
import android.content.ContextWrapper
import android.os.Build
import android.view.View
import android.view.Window
import android.view.WindowInsetsController
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.BoxScope
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ExperimentalLayoutApi
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.PaddingValues
import androidx.compose.foundation.layout.WindowInsets
import androidx.compose.foundation.layout.WindowInsetsSides
import androidx.compose.foundation.layout.displayCutout
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.only
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.statusBarsIgnoringVisibility
import androidx.compose.foundation.layout.systemBars
import androidx.compose.foundation.layout.union
import androidx.compose.foundation.layout.windowInsetsPadding
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.verticalScroll
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.SideEffect
import androidx.compose.runtime.Stable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableIntStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.runtime.staticCompositionLocalOf
import androidx.compose.ui.Modifier
import androidx.compose.ui.platform.LocalView
import androidx.compose.ui.unit.dp
import com.esuiss.ui.theme.EsuissTheme
import com.esuiss.ui.theme.Typography

@Stable
internal class KeyboardAccessoryInset {
    var height by mutableIntStateOf(0)
}

internal val LocalKeyboardAccessory = staticCompositionLocalOf<KeyboardAccessoryInset?> { null }

enum class ScreenEdge { Top, Bottom, Left, Right }

enum class ScreenVariant { Default, Secondary }

private val AllScreenEdges = setOf(ScreenEdge.Top, ScreenEdge.Bottom, ScreenEdge.Left, ScreenEdge.Right)

private fun Set<ScreenEdge>.sides(): WindowInsetsSides? = map {
    when (it) {
        ScreenEdge.Top -> WindowInsetsSides.Top
        ScreenEdge.Bottom -> WindowInsetsSides.Bottom
        ScreenEdge.Left -> WindowInsetsSides.Left
        ScreenEdge.Right -> WindowInsetsSides.Right
    }
}.reduceOrNull { sides, side -> sides + side }

internal tailrec fun Context.findActivity(): Activity? = when (this) {
    is Activity -> this
    is ContextWrapper -> baseContext.findActivity()
    else -> null
}

@Suppress("DEPRECATION")
private fun Window.applyLightBars(light: Boolean) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
        val mask = WindowInsetsController.APPEARANCE_LIGHT_STATUS_BARS or WindowInsetsController.APPEARANCE_LIGHT_NAVIGATION_BARS
        insetsController?.setSystemBarsAppearance(if (light) mask else 0, mask)
        return
    }
    var flags = decorView.systemUiVisibility
    flags = if (light) flags or View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR else flags and View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR.inv()
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        flags = if (light) flags or View.SYSTEM_UI_FLAG_LIGHT_NAVIGATION_BAR else flags and View.SYSTEM_UI_FLAG_LIGHT_NAVIGATION_BAR.inv()
    }
    if (decorView.systemUiVisibility != flags) decorView.systemUiVisibility = flags
}

@OptIn(ExperimentalLayoutApi::class)
@Composable
fun Screen(
    modifier: Modifier = Modifier,
    edges: Set<ScreenEdge> = AllScreenEdges,
    variant: ScreenVariant = ScreenVariant.Default,
    content: @Composable BoxScope.() -> Unit,
) {
    val colors = EsuissTheme.colors
    val view = LocalView.current
    val light = !colors.isDark
    SideEffect {
        if (!view.isInEditMode) view.context.findActivity()?.window?.applyLightBars(light)
    }
    val sides = edges.sides()
    val accessory = remember { KeyboardAccessoryInset() }
    val fill = when (variant) {
        ScreenVariant.Default -> colors.surface
        ScreenVariant.Secondary -> colors.surfaceSecondary
    }
    Box(
        modifier = modifier
            .fillMaxSize()
            .background(fill)
            .then(
                if (sides != null) {
                    Modifier.windowInsetsPadding(WindowInsets.systemBars.union(WindowInsets.displayCutout).union(WindowInsets.statusBarsIgnoringVisibility).only(sides))
                } else {
                    Modifier
                },
            ),
    ) {
        CompositionLocalProvider(
            LocalKeyboardAccessory provides accessory,
            LocalContentStyle provides Typography.base.copy(color = colors.label),
            LocalContentColor provides colors.label,
        ) {
            content()
        }
    }
}

@Composable
fun ScreenContent(
    modifier: Modifier = Modifier,
    scrollable: Boolean = false,
    contentPadding: PaddingValues = PaddingValues(16.dp),
    verticalArrangement: Arrangement.Vertical = Arrangement.spacedBy(16.dp),
    content: @Composable ColumnScope.() -> Unit,
) {
    Column(
        modifier = modifier
            .fillMaxWidth()
            .then(if (scrollable) Modifier.verticalScroll(rememberScrollState()) else Modifier)
            .padding(contentPadding),
        verticalArrangement = verticalArrangement,
        content = content,
    )
}
```

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

## Usage

```tsx
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
```

```tsx
<Page>
  <BottomBar>
    <BottomBarContent>
      <Button size="lg" block>
        <Text>Continue</Text>
      </Button>
    </BottomBarContent>
  </BottomBar>
</Page>
```

Place `BottomBar` as the last child of the screen so it sits below the scrolling content. Stack buttons in `BottomBarContent`, or add `flex-row` to place them side by side.

Set `separator` to draw a hairline above the bar. Inside a `Screen` that already handles the bottom safe-area edge, the inset is not added twice.

## Examples

### With separator

A hairline above the bar with `separator`.

![Preview](https://uim.suiss.app/previews/components-bottom-bar--with-separator.light.webp)

```tsx
import { View } from "react-native"
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
import { Button } from "@/components/ui/button"
import { Text } from "@/components/ui/text"

function Page({ children }: { children: React.ReactNode }) {
  return (
    <View className="-m-4 flex-1">
      <View className="flex-1 gap-2 p-4">
        <Text variant="h3">Review order</Text>
        <Text variant="muted">2 items, delivery on Thursday.</Text>
      </View>
      {children}
    </View>
  )
}

export function BottomBarWithSeparatorExample() {
  return (
    <Page>
      <BottomBar separator>
        <BottomBarContent>
          <Button size="lg" block>
            <Text>Place order</Text>
          </Button>
        </BottomBarContent>
      </BottomBar>
    </Page>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct BottomBarWithSeparatorExample: View {
  var body: some View {
    BottomBarPage {
      BottomBar(separator: true) {
        BottomBarContent {
          Button("Place order") {}.buttonStyle(.variant(size: .lg, block: true))
        }
      }
    }
  }
}

struct BottomBarPage<Bar: View>: View {
  @ViewBuilder let bar: () -> Bar

  var body: some View {
    VStack(spacing: 0) {
      VStack(alignment: .leading, spacing: 8) {
        Text("Review order").textVariant(.h3)
        Text("2 items, delivery on Thursday.").textVariant(.muted)
      }
      .padding(16)
      .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
      bar()
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.BottomBar
import com.esuiss.ui.components.BottomBarContent
import com.esuiss.ui.components.Button
import com.esuiss.ui.components.ButtonSize
import com.esuiss.ui.components.Screen
import com.esuiss.ui.components.ScreenEdge
import com.esuiss.ui.components.Text
import com.esuiss.ui.components.TextVariant

@Composable
fun BottomBarPage(page: @Composable ColumnScope.() -> Unit, bar: @Composable () -> Unit) {
    Screen(edges = setOf(ScreenEdge.Top, ScreenEdge.Left, ScreenEdge.Right)) {
        Column(Modifier.fillMaxSize()) {
            Column(
                Modifier.weight(1f).fillMaxWidth().padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
                content = page,
            )
            bar()
        }
    }
}

@Composable
fun BottomBarOrder(bar: @Composable () -> Unit) {
    BottomBarPage(
        page = {
            Text("Review order", variant = TextVariant.H3)
            Text("2 items, delivery on Thursday.", variant = TextVariant.Muted)
        },
        bar = bar,
    )
}

@Composable
fun BottomBarWithSeparator() {
    BottomBarOrder {
        BottomBar(separator = true) {
            BottomBarContent {
                Button("Place order", onClick = {}, size = ButtonSize.Lg, block = true)
            }
        }
    }
}
```

### Two actions

A primary and a plain button stacked.

![Preview](https://uim.suiss.app/previews/components-bottom-bar--two-actions.light.webp)

```tsx
import { View } from "react-native"
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
import { Button } from "@/components/ui/button"
import { Text } from "@/components/ui/text"

function Page({ children }: { children: React.ReactNode }) {
  return (
    <View className="-m-4 flex-1">
      <View className="flex-1 gap-2 p-4">
        <Text variant="h3">Review order</Text>
        <Text variant="muted">2 items, delivery on Thursday.</Text>
      </View>
      {children}
    </View>
  )
}

export function BottomBarTwoActionsExample() {
  return (
    <Page>
      <BottomBar separator>
        <BottomBarContent>
          <Button size="lg" block>
            <Text>Place order</Text>
          </Button>
          <Button size="lg" variant="plain" block>
            <Text>Save for later</Text>
          </Button>
        </BottomBarContent>
      </BottomBar>
    </Page>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct BottomBarTwoActionsExample: View {
  var body: some View {
    BottomBarPage {
      BottomBar(separator: true) {
        BottomBarContent {
          Button("Place order") {}.buttonStyle(.variant(size: .lg, block: true))
          Button("Save for later") {}.buttonStyle(.variant(.plain, size: .lg, block: true))
        }
      }
    }
  }
}

struct BottomBarPage<Bar: View>: View {
  @ViewBuilder let bar: () -> Bar

  var body: some View {
    VStack(spacing: 0) {
      VStack(alignment: .leading, spacing: 8) {
        Text("Review order").textVariant(.h3)
        Text("2 items, delivery on Thursday.").textVariant(.muted)
      }
      .padding(16)
      .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
      bar()
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.BottomBar
import com.esuiss.ui.components.BottomBarContent
import com.esuiss.ui.components.Button
import com.esuiss.ui.components.ButtonSize
import com.esuiss.ui.components.ButtonVariant
import com.esuiss.ui.components.Screen
import com.esuiss.ui.components.ScreenEdge
import com.esuiss.ui.components.Text
import com.esuiss.ui.components.TextVariant

@Composable
fun BottomBarPage(page: @Composable ColumnScope.() -> Unit, bar: @Composable () -> Unit) {
    Screen(edges = setOf(ScreenEdge.Top, ScreenEdge.Left, ScreenEdge.Right)) {
        Column(Modifier.fillMaxSize()) {
            Column(
                Modifier.weight(1f).fillMaxWidth().padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
                content = page,
            )
            bar()
        }
    }
}

@Composable
fun BottomBarOrder(bar: @Composable () -> Unit) {
    BottomBarPage(
        page = {
            Text("Review order", variant = TextVariant.H3)
            Text("2 items, delivery on Thursday.", variant = TextVariant.Muted)
        },
        bar = bar,
    )
}

@Composable
fun BottomBarTwoActions() {
    BottomBarOrder {
        BottomBar(separator = true) {
            BottomBarContent {
                Button("Place order", onClick = {}, size = ButtonSize.Lg, block = true)
                Button("Save for later", onClick = {}, size = ButtonSize.Lg, variant = ButtonVariant.Plain, block = true)
            }
        }
    }
}
```

### Side by side

Back and Next buttons in a row.

![Preview](https://uim.suiss.app/previews/components-bottom-bar--side-by-side.light.webp)

```tsx
import { View } from "react-native"
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
import { Button } from "@/components/ui/button"
import { Text } from "@/components/ui/text"

function Page({ children }: { children: React.ReactNode }) {
  return (
    <View className="-m-4 flex-1">
      <View className="flex-1 gap-2 p-4">
        <Text variant="h3">Review order</Text>
        <Text variant="muted">2 items, delivery on Thursday.</Text>
      </View>
      {children}
    </View>
  )
}

export function BottomBarSideBySideExample() {
  return (
    <Page>
      <BottomBar separator>
        <BottomBarContent className="flex-row">
          <Button size="lg" variant="secondary" block className="flex-1">
            <Text>Back</Text>
          </Button>
          <Button size="lg" block className="flex-1">
            <Text>Next</Text>
          </Button>
        </BottomBarContent>
      </BottomBar>
    </Page>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct BottomBarSideBySideExample: View {
  var body: some View {
    BottomBarPage {
      BottomBar(separator: true) {
        BottomBarContent {
          HStack(spacing: 8) {
            Button("Back") {}.buttonStyle(.variant(.secondary, size: .lg, block: true))
            Button("Next") {}.buttonStyle(.variant(size: .lg, block: true))
          }
        }
      }
    }
  }
}

struct BottomBarPage<Bar: View>: View {
  @ViewBuilder let bar: () -> Bar

  var body: some View {
    VStack(spacing: 0) {
      VStack(alignment: .leading, spacing: 8) {
        Text("Review order").textVariant(.h3)
        Text("2 items, delivery on Thursday.").textVariant(.muted)
      }
      .padding(16)
      .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
      bar()
    }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.BottomBar
import com.esuiss.ui.components.BottomBarContent
import com.esuiss.ui.components.Button
import com.esuiss.ui.components.ButtonSize
import com.esuiss.ui.components.ButtonVariant
import com.esuiss.ui.components.Screen
import com.esuiss.ui.components.ScreenEdge
import com.esuiss.ui.components.Text
import com.esuiss.ui.components.TextVariant

@Composable
fun BottomBarPage(page: @Composable ColumnScope.() -> Unit, bar: @Composable () -> Unit) {
    Screen(edges = setOf(ScreenEdge.Top, ScreenEdge.Left, ScreenEdge.Right)) {
        Column(Modifier.fillMaxSize()) {
            Column(
                Modifier.weight(1f).fillMaxWidth().padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
                content = page,
            )
            bar()
        }
    }
}

@Composable
fun BottomBarOrder(bar: @Composable () -> Unit) {
    BottomBarPage(
        page = {
            Text("Review order", variant = TextVariant.H3)
            Text("2 items, delivery on Thursday.", variant = TextVariant.Muted)
        },
        bar = bar,
    )
}

@Composable
fun BottomBarSideBySide() {
    BottomBarOrder {
        BottomBar(separator = true) {
            BottomBarContent {
                Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.spacedBy(8.dp)) {
                    Button("Back", onClick = {}, modifier = Modifier.weight(1f), size = ButtonSize.Lg, variant = ButtonVariant.Secondary, block = true)
                    Button("Next", onClick = {}, modifier = Modifier.weight(1f), size = ButtonSize.Lg, block = true)
                }
            }
        }
    }
}
```

### Above keyboard

The bar moving up with the keyboard while an input is focused.

![Preview](https://uim.suiss.app/previews/components-bottom-bar--above-keyboard.light.webp)

```tsx
import { View } from "react-native"
import { BottomBar, BottomBarContent } from "@/components/ui/bottom-bar"
import { Button } from "@/components/ui/button"
import { Input } from "@/components/ui/input"
import { Text } from "@/components/ui/text"

export function BottomBarAboveKeyboardExample() {
  return (
    <View className="-m-4 flex-1">
      <View className="flex-1 gap-3 p-4">
        <Text variant="h3">Promo code</Text>
        <Input placeholder="Enter code" autoFocus autoCapitalize="characters" />
      </View>
      <BottomBar separator>
        <BottomBarContent>
          <Button size="lg" block>
            <Text>Apply</Text>
          </Button>
        </BottomBarContent>
      </BottomBar>
    </View>
  )
}
```

```swift
import EsuissUI
import SwiftUI

struct BottomBarKeyboardDemo: View {
  @State private var code = ""
  @FocusState private var focused: Bool

  var body: some View {
    VStack(spacing: 0) {
      VStack(alignment: .leading, spacing: 12) {
        Text("Promo code").textVariant(.h3)
        TextField("Promo code", text: $code, prompt: Text("Enter code"))
          .textFieldStyle(.input)
          .textInputAutocapitalization(.characters)
          .focused($focused)
      }
      .padding(16)
      .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
      BottomBar(separator: true) {
        BottomBarContent {
          Button("Apply") {}.buttonStyle(.variant(size: .lg, block: true))
        }
      }
    }
    .onAppear { focused = true }
  }
}
```

```kotlin
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.ColumnScope
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.text.KeyboardOptions
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.saveable.rememberSaveable
import androidx.compose.runtime.setValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.focus.FocusRequester
import androidx.compose.ui.focus.focusRequester
import androidx.compose.ui.text.input.KeyboardCapitalization
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.BottomBar
import com.esuiss.ui.components.BottomBarContent
import com.esuiss.ui.components.Button
import com.esuiss.ui.components.ButtonSize
import com.esuiss.ui.components.Input
import com.esuiss.ui.components.Screen
import com.esuiss.ui.components.ScreenEdge
import com.esuiss.ui.components.Text
import com.esuiss.ui.components.TextVariant

@Composable
fun BottomBarPage(page: @Composable ColumnScope.() -> Unit, bar: @Composable () -> Unit) {
    Screen(edges = setOf(ScreenEdge.Top, ScreenEdge.Left, ScreenEdge.Right)) {
        Column(Modifier.fillMaxSize()) {
            Column(
                Modifier.weight(1f).fillMaxWidth().padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
                content = page,
            )
            bar()
        }
    }
}

@Composable
fun BottomBarAboveKeyboard() {
    var code by rememberSaveable { mutableStateOf("") }
    val focus = remember { FocusRequester() }
    LaunchedEffect(Unit) { focus.requestFocus() }
    BottomBarPage(
        page = {
            Column(verticalArrangement = Arrangement.spacedBy(12.dp)) {
                Text("Promo code", variant = TextVariant.H3)
                Input(
                    code,
                    { code = it },
                    Modifier.focusRequester(focus),
                    placeholder = "Enter code",
                    keyboardOptions = KeyboardOptions(capitalization = KeyboardCapitalization.Characters),
                )
            }
        },
        bar = {
            BottomBar(separator = true) {
                BottomBarContent {
                    Button("Apply", onClick = {}, size = ButtonSize.Lg, block = true)
                }
            }
        },
    )
}
```

## API Reference

### BottomBar

Bottom container that follows the safe area and keyboard.

### BottomBarContent

Padded area for the actions.

## Accessibility

- The bar adds no role; each action inside provides its own.

## Notes

- The padding animation respects the system Reduce Motion setting.
- Uses `bg-surface` and `border-separator` tokens; light and dark follow the system appearance.