Line Geometries
The [ObservableObject], [ObservableProperty] and [RelayCommand] attributes come from the
CommunityToolkit.Mvvm package, you can read more about it
here.
This web site wraps every sample using a ContentPage instance, but LiveCharts controls can be used inside any container.
View model
using CommunityToolkit.Mvvm.ComponentModel;
using LiveChartsCore;
using LiveChartsCore.Drawing;
using LiveChartsCore.SkiaSharpView;
using LiveChartsCore.SkiaSharpView.Drawing.Geometries;
namespace ViewModelsSamples.Lines.Custom;
public partial class ViewModel : ObservableObject
{
public ISeries[] Series { get; set; } =
{
new LineSeries<double>
{
Values = new double[] { 2, 1, 4, 2, 2, -5, -2 },
Fill = null,
GeometrySize = 20
},
// use the second type parameter to specify the geometry to draw for every point
// there are already many predefined geometries in the
// LiveChartsCore.SkiaSharpView.Drawing.Geometries namespace
new LineSeries<double, RectangleGeometry>
{
Values = new double[] { 3, 3, -3, -2, -4, -3, -1 },
Fill = null,
GeometrySize = 20
},
// You can also use SVG paths to draw the geometry
// LiveCharts already provides some predefined paths in the SVGPoints class.
new LineSeries<double, SVGPathGeometry>
{
Values = new double[] { -2, 2, 1, 3, -1, 4, 3 },
Fill = null,
GeometrySvg = SVGPoints.Star,
GeometrySize = 20
},
// you can declare your own gemetry and use the SkiaSharp api to draw it
new LineSeries<double, MyGeometry>
{
Values = new double[] { 4, 5, 2, 4, 3, 2, 1 },
Fill = null,
GeometrySize = 20
},
};
}
MyGeometry.cs
using LiveChartsCore.SkiaSharpView.Drawing;
using LiveChartsCore.SkiaSharpView.Drawing.Geometries;
using SkiaSharp;
namespace ViewModelsSamples.Lines.Custom;
public class MyGeometry : SizedGeometry
{
public override void OnDraw(SkiaSharpDrawingContext context, SKPaint paint)
{
var canvas = context.Canvas;
canvas.DrawRect(X, Y, Width, Height, paint);
canvas.DrawLine(X, Y, X + Width, Y + Height, paint);
canvas.DrawLine(X + Width, Y, X, Y + Height, paint);
}
}
XAML
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="XamarinSample.Lines.Custom.View"
xmlns:lvc="clr-namespace:LiveChartsCore.SkiaSharpView.Xamarin.Forms;assembly=LiveChartsCore.SkiaSharpView.XamarinForms"
xmlns:vms="clr-namespace:ViewModelsSamples.Lines.Custom;assembly=ViewModelsSamples">
<ContentPage.BindingContext>
<vms:ViewModel/>
</ContentPage.BindingContext>
<lvc:CartesianChart Series="{Binding Series}"/>
</ContentPage>
