About

Sankey diagrams in SwiftUI, powered by Google Charts^‡

Quickstart

Make interactive charts like this:

With code as simple as this:

import Sankey
import SwiftUI

struct ReadMeView: View {
    // Create some data
    @State var data: [SankeyLink] = [
        // Option A: ExpressibleByArrayLiteral
        ["A", "X", "5"],
        ["A", "Y", "7"],
        ["A", "Z", "6"],
        ["B", "X", "2"],
        ["B", "Y", "9"],
        ["B", "Z", "4"]
    ]

    var body: some View {
        GeometryReader { geo in
            VStack(spacing: 20) {
                Text("Sankeys in SwiftUI!")
                    .font(.title3.bold())
                    .padding(.top, 20)
                // Native SwiftUI Component
                SankeyDiagram(
                    data,
                    nodeLabelFontSize: 50,
                    nodeInteractivity: true,
                    linkColorMode: .gradient,
                    tooltipTextFontSize: 50
                )
                // Will take up full View, unless you constrain it...
                .frame(height: geo.size.height * 0.5)
                Button {
                    data.append(
                        // Option B: Struct
                        SankeyLink(source: "C", target: "X", value: 3)
                    )
                } label: {
                    Text("Add a new link")
                }
                Text("Lorem Ipsum...")
            }
        }
    }
}

Examples

Inspired by the examples in the Google Charts Gallery

• Simple Sankey | Code | Inspiration

SankeyDiagram([
    ["A", "X", "5"],
    ["A", "Y", "7"],
    ["A", "Z", "6"],
    ["B", "X", "2"],
    ["B", "Y", "9"],
    ["B", "Z", "4"]
])

• Multilevel Sankey | Code | Inspiration

SankeyDiagram(data)

• Gradient Links | Code | Inspiration

let colors = [
    "#a6cee3", "#b2df8a", "#fb9a99", "#fdbf6f",
    "#cab2d6", "#ffff99", "#1f78b4", "#33a02c"
]	

SankeyDiagram(
    data,
    nodeColors: colors,
    linkColors: colors,
    linkColorMode: .gradient
)

• Uniform Color | Code | Inspiration

SankeyDiagram(
    data,
    nodeColors: ["#a61d4c"],
    nodeLabelColor: "#871b47",
    linkColorFill: "#d799ae",
    linkColorFillOpacity: 0.8
)

• Stroked Links | Code | Inspiration

SankeyDiagram(
    data,
    nodeColors: ["#a61d4c"],
    linkColorStroke: "black",
    linkColorStrokeWidth: 1
)

• Label Style | Code | Inspiration

SankeyDiagram(
    data,
    nodeLabelColor: "#871b47",
    nodeLabelFontSize: 32,
    nodeLabelFontName: "Times-Roman",
    nodeLabelBold: true,
    nodeLabelItalic: true
)

• Label Padding | Code | Inspiration

SankeyDiagram(
    data,
    nodeLabelPadding: 30
)

• Node Width | Code | Inspiration

SankeyDiagram(
    data,
    nodeWidth: 24
)

• Node Padding | Code | Inspiration

SankeyDiagram(
    data,
    nodePadding: 40
)

• Data | Code | Inspiration

let data: [SankeyLink] = [
    ["Brazil", "Portugal", "5"],
    ["Brazil", "France", "1"],
    ["Brazil", "Spain", "1"],
    ["Brazil", "England", "1"],
    ["Canada", "Portugal", "1"],
    ["Canada", "France", "5"],
    ["Canada", "England", "1"],
    ["Mexico", "Portugal", "1"],
    ["Mexico", "France", "1"],
    ["Mexico", "Spain", "5"],
    ["Mexico", "England", "1"],
    ["USA", "Portugal", "1"],
    ["USA", "France", "1"],
    ["USA", "Spain", "1"],
    ["USA", "England", "5"],
    ["Portugal", "Angola", "2"],
    ["Portugal", "Senegal", "1"],
    ["Portugal", "Morocco", "1"],
    ["Portugal", "South Africa", "3"],
    ["France", "Angola", "1"],
    ["France", "Senegal", "3"],
    ["France", "Mali", "3"],
    ["France", "Morocco", "3"],
    ["France", "South Africa", "1"],
    ["Spain", "Senegal", "1"],
    ["Spain", "Morocco", "3"],
    ["Spain", "South Africa", "1"],
    ["England", "Angola", "1"],
    ["England", "Senegal", "1"],
    ["England", "Morocco", "2"],
    ["England", "South Africa", "7"],
    ["South Africa", "China", "5"],
    ["South Africa", "India", "1"],
    ["South Africa", "Japan", "3"],
    ["Angola", "China", "5"],
    ["Angola", "India", "1"],
    ["Angola", "Japan", "3"],
    ["Senegal", "China", "5"],
    ["Senegal", "India", "1"],
    ["Senegal", "Japan", "3"],
    ["Mali", "China", "5"],
    ["Mali", "India", "1"],
    ["Mali", "Japan", "3"],
    ["Morocco", "China", "5"],
    ["Morocco", "India", "1"],
    ["Morocco", "Japan", "3"]
]

API

Optional SankeyDiagram(data, ...) styling arguments :

Argument:	Default	Description
nodeColors	[String]? = nil	Custom color (hexcodes) palette to cycle through for sankey nodes
nodeColorMode	SankeyOptions.Sankey.Node.ColorMode = .unique	Coloring mode for the sankey nodes
nodeWidth	Double? = nil	Thickness of the node
nodePadding	Double? = nil	Vertical distance between nodes
nodeLabelColor	String = "black"	Node label color (hexcode/html)
nodeLabelFontSize	Double = 24	Node label font size (pixels)
nodeLabelFontName	String? = nil	Node label font name
nodeLabelBold	Bool = false	Bold node label
nodeLabelItalic	Bool = false	Italicize node label
nodeLabelPadding	Double? = nil	Horizontal distance between the label and the node
nodeInteractivity	Bool = false	Allow users to select node
linkColors	[String]? = nil	Custom color (hexcode) palette to cycle through for sankey links
linkColorMode	SankeyOptions.Sankey.Link.ColorMode? = nil	Coloring mode for the links between nodes (this option will override any linkColor+ argument)
linkColorFill	String? = nil	Color of the link
linkColorFillOpacity	Double? = nil	Transparency of the link
linkColorStroke	String? = nil	Color of the link border
linkColorStrokeWidth	Double = 0	Thickness of the link border
tooltipValueLabel	String = ""	Name of the link value to be displayed in the tooltip
tooltipTextColor	String = "black"	Tooltip text color (html/hexcode)
tooltipTextFontSize	Double = 24	Tooltip text font size (pixels)
tooltipTextFontName	String? = nil	Tooltip text font name
tooltipTextBold	Bool = false	Bold tooltip label text
tooltipTextItalic	Bool = false	Italicize tooltip label text
layoutIterations	Int = 32	D3 layout engine layout search attempts to find the most optimal node positions (increasing this number may lead to more pleasing layouts of complex sankeys, at some cost)

For more information see configuration options

Swift Package Manager

Add to your project with:

dependencies: [
    .package(url: "https://github.com/maxhumber/Sankey.git", .upToNextMajor(from: "1.0"))
]

Fine Print

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