How to Create Charts on iOS using SwiftUI

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How to Create Charts on iOS using SwiftUI

Spruce up your app with Apple's built-in Charts library

·

2 min read

SwiftUI Natively Supports Charting

Starting with iOS 16, iPadOS 16, and watchOS 9, SwiftUI supports the native creation of charts. Before those versions were released in 2022, creating a chart required tons of development work or an outside dependency.

Requirements

Creating charts using SwiftUI requires developing an iOS app targeted at iOS 16 and above.

Charts requires a version about iOS 16

Mark Types

Mark types are used to plot data onto charts. Apple defines six mark types.

How to Create a Basic Bar Chart

Every chart starts with a Chart view. The Chart view is the container for the data. Inside the Chart view, you can start providing data using one of Apple's predefined marks.

Chart {
    BarMark(
        x: .value("Type", "Swift"),
        y: .value("Total Count", 5)
    )
    BarMark(
        x: .value("Type", "UI"),
        y: .value("Total Count", 4)
    )
    BarMark(
        x: .value("Type", "Chart"),
        y: .value("Total Count", 3)
    )
 }

A basic SwiftUI bar chart example

A more advanced bar graph example can be found over on my Github.

Created a color SwiftUI bar chart

How to Create a Line Graph

A line graph can be created by using LineMark inside a Chart view.

Chart {
    LineMark(
        x: .value("Type", "Swift"),
        y: .value("Total Count", 5)
    )
    LineMark(
        x: .value("Type", "UI"),
        y: .value("Total Count", 4)
    )
    LineMark(
        x: .value("Type", "Chart"),
        y: .value("Total Count", 3)
    )
 }

Creating a line chart requires using LineMark

How to Create a Scatter Plot

Finally, a scatter graph can be created by using PointMark inside a Chart view.

Chart {
    PointMark(
        x: .value("Type", "Swift"),
        y: .value("Total Count", 5)
    )
    PointMark(
        x: .value("Type", "UI"),
        y: .value("Total Count", 4)
    )
    PointMark(
        x: .value("Type", "Chart"),
        y: .value("Total Count", 3)
    )
 }

image.png

How to Label Chart Data

  • Data can be labeled using a PlottableValue.
    PointMark(
        x: .value("Type", "Swift"),
        y: .value("Total Count", 5)
    ).foregroundStyle(by: .value("Series", "Swift"))
    

Conclusion

SwiftUI Charts is a powerful and easy-to-use option that brings crucial functionality to native support. Try including it in your next app hacking project.

Sources

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