Easy to use and highly customizable pie charts library for iOS

Swift 4.2, iOS 8+

Video

• Customizable slices
• Add overlays using simple UIViews
• Interactive
• Animated
• Dynamic slice insertion
• Reusable components via extensible layer system
• Configurable in interface builder
• Legends. This is in a separate project to keep things focused and reusable.

Add to your Podfile:

use_frameworks!
pod 'PieCharts'

Add to your Cartfile:

github "i-schuetz/PieCharts"

@IBOutlet weak var chartView: PieChart!

chartView.models = [
    PieSliceModel(value: 2.1, color: UIColor.yellow),
    PieSliceModel(value: 3, color: UIColor.blue),
    PieSliceModel(value: 1, color: UIColor.green)
]

Configurable in interface builder, with live update of the view:

Overlays are implemented using layers. There are several built in layers and you also can implement your own ones.

To add text e.g. text labels inside the slices + text with lines outside, simply:

chartView.layers = [PiePlainTextLayer(), PieLineTextLayer()]

Each layer has its own customization options. For example, here we customize the plain labels layer:

let textLayerSettings = PiePlainTextLayerSettings()
textLayerSettings.viewRadius = 55
textLayerSettings.hideOnOverflow = true
textLayerSettings.label.font = UIFont.systemFont(ofSize: 8)

let formatter = NumberFormatter()
formatter.maximumFractionDigits = 1
textLayerSettings.label.textGenerator = {slice in
    return formatter.string(from: slice.data.percentage * 100 as NSNumber).map{"\($0)%"} ?? ""
}

let textLayer = PiePlainTextLayer()
textLayer.animator = AlphaPieViewLayerAnimator()
textLayer.settings = textLayerSettings

This is the custom views layer, which makes possible to create custom views:

let viewLayer = PieCustomViewsLayer()

let settings = PieCustomViewsLayerSettings()
settings.viewRadius = 135
settings.hideOnOverflow = false
viewLayer.settings = settings

viewLayer.viewGenerator = {slice, center in
    let myView = UIView()
    // add images, animations, etc.
    return myView
}

Conform to PieChartDelegate to react to interaction and other events:

func onGenerateSlice(slice: PieSlice)
func onStartAnimation(slice: PieSlice)
func onEndAnimation(slice: PieSlice)
func onSelected(slice: PieSlice, selected: Bool)

chartView.insertSlice(index: 1, model: PieSliceModel(value: 5, color: UIColor.blue))

1. Fork
2. Commit changes to a branch in your fork
3. Push your code and make a pull request

The layer system can be abstracted a step further in order to make the slices themselves be in a layer. This way we can combine multiple slice-layers to create more complex types of pie charts.

The food images used in the demo are from freepik.com, and flaticon.com/authors/madebyoliver

Ivan Schütz

SwiftCharts is Copyright (c) 2017 Ivan Schütz and released as open source under the attached Apache 2.0 license.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.