Line Chart Forecast

A twelve-month line with actual values in solid and a forecast in dashed, over a shaded future range.

Line Chart Forecast is an open-source mobile chart from suiss/uim, drawn with react-native-svg 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.

iOS

uniwind/components/charts/line-chart-forecast.tsx

import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card"
import {
  CartesianGrid,
  type ChartConfig,
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
  Line,
  LineChart,
  ReferenceArea,

swift/Charts/LineChartForecast.swift

import Charts
import SwiftUI

private let actual: [Double] = [12, 14, 13, 17, 19, 22, 24, 23, 26]
private let forecast: [Double] = [26, 28, 30, 33]
private let months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]

private let chartConfig: ChartConfig = [
  "actual": .init("Actual", color: .blue),
  "forecast": .init("Forecast", color: .blue),
]

private func value(_ key: String, _ index: Int) -> Double? {
  if key == "actual" { return actual.indices.contains(index) ? actual[index] : nil }
  return index >= 8 ? forecast[index - 8] : nil
}

kotlin/charts/LineChartForecast.kt

package com.esuiss.ui.charts

import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Card
import com.esuiss.ui.components.CardContent
import com.esuiss.ui.components.CardHeader
import com.esuiss.ui.components.CardSize
import com.esuiss.ui.components.CardVariant
import com.esuiss.ui.components.ChartConfig
import com.esuiss.ui.components.ChartConfigItem
import com.esuiss.ui.components.ChartContainer
import com.esuiss.ui.components.ChartCurve

Two series share one axis: actual fills the first nine months and forecast continues from September, drawn with strokeDasharray. A ReferenceArea shades September to December to mark the forecast period. Missing values are null, so each line stops where its data ends.

Installation

$ pnpm dlx @esuiss/uim@latest add line-chart-forecast

The CLI also adds what it builds on: Card, Chart.

Manual

Add the pieces it builds on: Card, Chart.
Copy the source into components/charts/line-chart-forecast.tsx:

uniwind/components/charts/line-chart-forecast.tsx

import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card"
import {
  CartesianGrid,
  type ChartConfig,
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
  Line,
  LineChart,
  ReferenceArea,

Update the import paths to match your project.

Add the pieces it builds on: Card, Chart.
Copy the source into components/charts/line-chart-forecast.tsx:

nativewind/components/charts/line-chart-forecast.tsx

import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card"
import {
  CartesianGrid,
  type ChartConfig,
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
  Line,
  LineChart,
  ReferenceArea,

Update the import paths to match your project.

Add the pieces it builds on: Card, Chart.
Copy the source into components/charts/line-chart-forecast.tsx:

stylesheet/components/charts/line-chart-forecast.tsx

import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card"
import {
  CartesianGrid,
  type ChartConfig,
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
  Line,
  LineChart,
  ReferenceArea,

Update the import paths to match your project.

Target iOS 17 or later.
Copy the theme files every view uses:

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
  }

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))

Copy the source and every file it uses:

swift/Charts/LineChartForecast.swift

import Charts
import SwiftUI

private let actual: [Double] = [12, 14, 13, 17, 19, 22, 24, 23, 26]
private let forecast: [Double] = [26, 28, 30, 33]
private let months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]

private let chartConfig: ChartConfig = [
  "actual": .init("Actual", color: .blue),
  "forecast": .init("Forecast", color: .blue),
]

private func value(_ key: String, _ index: Int) -> Double? {
  if key == "actual" { return actual.indices.contains(index) ? actual[index] : nil }
  return index >= 8 ? forecast[index - 8] : nil
}

swift/Components/Card.swift

import SwiftUI

public struct Card<Content: View>: View {
  public enum Variant: CaseIterable, Sendable {
    case `default`, filled
  }

  public enum Size: CaseIterable, Sendable {
    case `default`, sm

    var spacing: CGFloat {
      switch self {
      case .default: 24
      case .sm: 16
      }
    }

swift/Components/Chart.swift

import Charts
import SwiftUI

public struct ChartConfig: ExpressibleByDictionaryLiteral, Sendable {
  public struct Item: Sendable {
    public var label: String?
    public var color: Color?
    public var icon: Image?

    public init(_ label: String? = nil, color: Color? = nil, icon: Image? = nil) {
      self.label = label
      self.color = color
      self.icon = icon
    }
  }

swift/Components/Haptics.swift

import SwiftUI

extension EnvironmentValues {
  @Entry public var hapticsEnabled = true
}

extension View {
  public func haptics(_ enabled: Bool) -> some View {
    environment(\.hapticsEnabled, enabled)
  }

  func hapticFeedback<Trigger: Equatable>(_ feedback: SensoryFeedback, trigger: Trigger) -> some View {
    modifier(HapticFeedbackModifier(feedback: feedback, trigger: trigger) { _, _ in true })
  }

  func hapticFeedback<Trigger: Equatable>(

swift/Components/Item.swift

import SwiftUI

public enum ItemVariant: CaseIterable, Sendable {
  case `default`, outline, muted
}

public enum ItemSize: CaseIterable, Sendable {
  case `default`, sm, xs

  var horizontalPadding: CGFloat {
    switch self {
    case .default: 16
    case .sm: 14
    case .xs: 12
    }
  }

swift/Components/Separator.swift

import SwiftUI

public struct Separator: View {
  let orientation: Axis

  public init(_ orientation: Axis = .horizontal) {
    self.orientation = orientation
  }

  public var body: some View {
    Rectangle()
      .fill(Color.separator)
      .frame(width: orientation == .vertical ? 1 : nil, height: orientation == .horizontal ? 1 : nil)
      .frame(maxWidth: orientation == .horizontal ? .infinity : nil, maxHeight: orientation == .vertical ? .infinity : nil)
      .accessibilityHidden(true)
  }

swift/Components/TextVariant.swift

import SwiftUI

public enum TextVariant: CaseIterable, Sendable {
  case `default`, h1, h2, h3, h4, p, blockquote, code, lead, large, small, muted

  var style: TextStyle {
    switch self {
    case .h1: .xl3
    case .h2: .xl2
    case .h3: .xl
    case .h4, .lead, .large: .lg
    case .code, .small, .muted: .sm
    default: .base
    }
  }

Add the files to your app target.

Set minSdk to 24 or higher and add the dependencies:

build.gradle.kts

implementation(platform("androidx.compose:compose-bom:2026.09.00"))
implementation("androidx.compose.foundation:foundation")
implementation("androidx.compose.ui:ui")

Copy the theme files every view uses:

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

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,

Copy the source and every file it uses:

kotlin/charts/LineChartForecast.kt

package com.esuiss.ui.charts

import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import com.esuiss.ui.components.Card
import com.esuiss.ui.components.CardContent
import com.esuiss.ui.components.CardHeader
import com.esuiss.ui.components.CardSize
import com.esuiss.ui.components.CardVariant
import com.esuiss.ui.components.ChartConfig
import com.esuiss.ui.components.ChartConfigItem
import com.esuiss.ui.components.ChartContainer
import com.esuiss.ui.components.ChartCurve

kotlin/components/Card.kt

package com.esuiss.ui.components

import androidx.compose.foundation.background
import androidx.compose.foundation.border
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.RowScope
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.foundation.text.BasicText
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.compositionLocalOf

kotlin/components/Chart.kt

package com.esuiss.ui.components

import androidx.compose.animation.core.Animatable
import androidx.compose.animation.core.CubicBezierEasing
import androidx.compose.animation.core.Easing
import androidx.compose.animation.core.LinearEasing
import androidx.compose.animation.core.tween
import androidx.compose.foundation.Canvas
import androidx.compose.foundation.background
import androidx.compose.foundation.border
import androidx.compose.foundation.gestures.detectHorizontalDragGestures
import androidx.compose.foundation.gestures.detectTapGestures
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.BoxScope
import androidx.compose.foundation.layout.BoxWithConstraints

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 }

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

kotlin/components/Haptics.kt

package com.esuiss.ui.components

import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.remember
import androidx.compose.runtime.staticCompositionLocalOf
import androidx.compose.ui.hapticfeedback.HapticFeedback
import androidx.compose.ui.hapticfeedback.HapticFeedbackType
import androidx.compose.ui.platform.LocalHapticFeedback

val LocalHapticsEnabled = staticCompositionLocalOf { true }

@Composable
fun ProvideHaptics(enabled: Boolean, content: @Composable () -> Unit) {
    CompositionLocalProvider(LocalHapticsEnabled provides enabled, content = content)
}

kotlin/components/Icon.kt

package com.esuiss.ui.components

import androidx.compose.foundation.Image
import androidx.compose.foundation.layout.size
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.ColorFilter
import androidx.compose.ui.graphics.takeOrElse
import androidx.compose.ui.graphics.vector.ImageVector
import androidx.compose.ui.unit.Dp
import com.esuiss.ui.theme.EsuissTheme

@Composable
fun Icon(
    imageVector: ImageVector,

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

Usage

import { LineChartForecast } from "@/components/charts/line-chart-forecast"

<LineChartForecast />

Replace the actual and forecast arrays; the forecast starts at the index set in chartData. Move the ReferenceArea x1 and x2 to match your forecast range. The component takes no props.